diff --git a/include/boost/program_options/detail/value_semantic.hpp b/include/boost/program_options/detail/value_semantic.hpp
index 06c9849..464e306 100644
--- a/include/boost/program_options/detail/value_semantic.hpp
+++ b/include/boost/program_options/detail/value_semantic.hpp
@@ -55,11 +55,11 @@ namespace boost { namespace program_options {
         {
             static std::basic_string<charT> empty;
             if (v.size() > 1)
-                boost::throw_exception(validation_error("multiple values not allowed"));
+                boost::throw_exception(validation_error(validation_error::multiple_values_not_allowed));
             else if (v.size() == 1)
                 return v.front();
             else if (!allow_empty)
-              boost::throw_exception(validation_error("at least one value required"));
+                boost::throw_exception(validation_error(validation_error::at_least_one_value_required));
             return empty;
         }
 
diff --git a/include/boost/program_options/errors.hpp b/include/boost/program_options/errors.hpp
index 938f8eb..3da1709 100644
--- a/include/boost/program_options/errors.hpp
+++ b/include/boost/program_options/errors.hpp
@@ -25,17 +25,33 @@ namespace boost { namespace program_options {
 
     class BOOST_PROGRAM_OPTIONS_DECL invalid_syntax : public error {
     public:
-        invalid_syntax(const std::string& tokens, const std::string& msg)
-        : error(std::string(msg).append(" in '").append(tokens).append("'")),
-          tokens(tokens), msg(msg)                       
-        {}
+        enum kind_t {
+            long_not_allowed = 30,
+            long_adjacent_not_allowed,
+            short_adjacent_not_allowed,
+            empty_adjacent_parameter,
+            missing_parameter,
+            extra_parameter,
+            unrecognized_line
+        };
+        
+        invalid_syntax(const std::string& tokens, kind_t kind);
 
         // gcc says that throw specification on dtor is loosened
         // without this line
         ~invalid_syntax() throw() {}
+        
+        kind_t kind() const;
+        
+    protected:
+        /** Used to convert kind_t to a related error text */
+        static std::string error_message(kind_t kind);
 
+    private:
         // TODO: copy ctor might throw
-        std::string tokens, msg;
+        std::string m_tokens;
+
+        kind_t m_kind;
     };
 
     /** Class thrown when option name is not recognized. */
@@ -50,12 +66,10 @@ namespace boost { namespace program_options {
         // without this line
         ~unknown_option() throw() {}
         
-        const std::string& get_option_name() const throw()
-        { 
-           return m_option_name; 
-        }
+        const std::string& get_option_name() const throw();
+        
     private:
-       std::string m_option_name;
+        std::string m_option_name;
     };
 
     /** Class thrown when there's ambiguity amoung several possible options. */
@@ -63,30 +77,35 @@ namespace boost { namespace program_options {
     public:
         ambiguous_option(const std::string& name, 
                          const std::vector<std::string>& alternatives)
-        : error(std::string("ambiguous option ").append(name)),
-          alternatives(alternatives)
+        : error(std::string("ambiguous option ").append(name))
+        , alternatives(alternatives)
+        , m_option_name(name)
         {}
 
         ~ambiguous_option() throw() {}
+        
+        const std::string& get_option_name() const throw();
 
+    private:
         // TODO: copy ctor might throw
         std::vector<std::string> alternatives;
+        std::string m_option_name;
     };
 
     /** Class thrown when there are several option values, but
         user called a method which cannot return them all. */
     class BOOST_PROGRAM_OPTIONS_DECL multiple_values : public error {
     public:
-        multiple_values(const std::string& what) 
-         : error(what), m_option_name() {}
+        multiple_values() 
+         : error("multiple values")
+         , m_option_name() {}
+         
         ~multiple_values() throw() {}
         
         void set_option_name(const std::string& option);
         
-        const std::string& get_option_name() const throw()
-        {
-           return m_option_name;
-        }
+        const std::string& get_option_name() const throw();
+        
     private:
         std::string m_option_name; // The name of the option which
                                    // caused the exception.        
@@ -97,16 +116,15 @@ namespace boost { namespace program_options {
         them all. */
     class BOOST_PROGRAM_OPTIONS_DECL multiple_occurrences : public error {
     public:
-        multiple_occurrences(const std::string& what) 
-         : error(what), m_option_name() {}
+        multiple_occurrences() 
+         : error("multiple occurrences")
+         , m_option_name() {}
+         
         ~multiple_occurrences() throw() {}
         
         void set_option_name(const std::string& option);
         
-        const std::string& get_option_name() const throw()
-        {
-           return m_option_name;
-        }
+        const std::string& get_option_name() const throw();
 
     private:        
         std::string m_option_name; // The name of the option which
@@ -116,22 +134,40 @@ namespace boost { namespace program_options {
     /** Class thrown when value of option is incorrect. */
     class BOOST_PROGRAM_OPTIONS_DECL validation_error : public error {
     public:
-        validation_error(const std::string& what) : error(what) {}
+        enum kind_t {
+            multiple_values_not_allowed = 30,
+            at_least_one_value_required, 
+            invalid_bool_value,
+            invalid_option_value,
+            invalid_option
+        };
+        
+        validation_error(kind_t kind, 
+                         const std::string& option_value = "",
+                         const std::string& option_name = "");
+                         
         ~validation_error() throw() {}
+
         void set_option_name(const std::string& option);
         
-        const std::string& get_option_name() const throw()
-        {
-           return m_option_name;
-        }
+        const std::string& get_option_name() const throw();
         
         const char* what() const throw();
+        
+    protected:
+        /** Used to convert kind_t to a related error text */
+        static std::string error_message(kind_t kind);
+
     private:
-        mutable std::string m_message; // For on-demand formatting in 'what'
+        kind_t m_kind;
         std::string m_option_name; // The name of the option which
                                    // caused the exception.
+        std::string m_option_value; // Optional: value of the option m_options_name
+        mutable std::string m_message; // For on-demand formatting in 'what'
+
     };
 
+    /** Class thrown if there is an invalid option value givenn */
     class BOOST_PROGRAM_OPTIONS_DECL invalid_option_value 
         : public validation_error
     {
@@ -142,39 +178,23 @@ namespace boost { namespace program_options {
 #endif
     };
 
-    /** Class thrown when there are too many positional options. */
+    /** Class thrown when there are too many positional options. 
+        This is a programming error.
+    */
     class BOOST_PROGRAM_OPTIONS_DECL too_many_positional_options_error : public error {
     public:
-        too_many_positional_options_error(const std::string& what) 
-        : error(what) {}
-    };
-
-    /** Class thrown when there are too few positional options. */
-    class BOOST_PROGRAM_OPTIONS_DECL too_few_positional_options_error : public error {
-    public:
-        too_few_positional_options_error(const std::string& what) 
-        : error(what) {}
+        too_many_positional_options_error() 
+         : error("too many positional options") 
+        {}
     };
 
+    /** Class thrown when there are syntax errors in given command line */
     class BOOST_PROGRAM_OPTIONS_DECL invalid_command_line_syntax : public invalid_syntax {
     public:
-        enum kind_t {
-            long_not_allowed = 30,
-            long_adjacent_not_allowed,
-            short_adjacent_not_allowed,
-            empty_adjacent_parameter,
-            missing_parameter,
-            extra_parameter
-        };
-
         invalid_command_line_syntax(const std::string& tokens, kind_t kind);
-        kind_t kind() const;
-    protected:
-        static std::string error_message(kind_t kind);
-    private:
-        kind_t m_kind;        
     };
 
+    /** Class thrown when there are programming error related to style */
     class BOOST_PROGRAM_OPTIONS_DECL invalid_command_line_style : public error {
     public:
         invalid_command_line_style(const std::string& msg)
diff --git a/src/cmdline.cpp b/src/cmdline.cpp
index 2d90bae..8f8800f 100644
--- a/src/cmdline.cpp
+++ b/src/cmdline.cpp
@@ -34,13 +34,15 @@ namespace boost { namespace program_options {
     using namespace std;
     using namespace boost::program_options::command_line_style;
     
-    invalid_command_line_syntax::
-    invalid_command_line_syntax(const std::string& tokens, kind_t kind)
-    : invalid_syntax(tokens, error_message(kind)), m_kind(kind)
+    invalid_syntax::
+    invalid_syntax(const std::string& tokens, kind_t kind)
+     : error(error_message(kind).append(" in '").append(tokens).append("'"))
+     , m_tokens(tokens)
+     , m_kind(kind)                       
     {}
-
+    
     std::string 
-    invalid_command_line_syntax::error_message(kind_t kind)
+    invalid_syntax::error_message(kind_t kind)
     {
         // Initially, store the message in 'const char*' variable,
         // to avoid conversion to std::string in all cases.
@@ -65,18 +67,25 @@ namespace boost { namespace program_options {
         case extra_parameter:
             msg = "extra parameter";
             break;
+        case unrecognized_line:
+            msg = "unrecognized line";
+            break;
         default:
             msg = "unknown error";
         }
         return msg;
     }
 
-    invalid_command_line_syntax::kind_t 
-    invalid_command_line_syntax::kind() const
+    invalid_syntax::kind_t 
+    invalid_syntax::kind() const
     {
         return m_kind;
     }
 
+    invalid_command_line_syntax::
+    invalid_command_line_syntax(const std::string& tokens, kind_t kind)
+    : invalid_syntax(tokens, kind)
+    {}
 
 }}
 
@@ -326,8 +335,7 @@ namespace boost { namespace program_options { namespace detail {
                 if (opt.position_key != -1) {
                     if (position >= m_positional->max_total_count())
                     {
-                        boost::throw_exception(too_many_positional_options_error(
-                                               "too many positional options"));
+                        boost::throw_exception(too_many_positional_options_error());
                     }
                     opt.string_key = m_positional->name_for_position(position);
                     ++position;
diff --git a/src/config_file.cpp b/src/config_file.cpp
index 048c010..434ad10 100644
--- a/src/config_file.cpp
+++ b/src/config_file.cpp
@@ -114,7 +114,7 @@ namespace boost { namespace program_options { namespace detail {
                     break;
 
                 } else {
-                    boost::throw_exception(invalid_syntax(s, "unrecognized line"));
+                    boost::throw_exception(invalid_syntax(s, invalid_syntax::unrecognized_line));
                 }
             }
         }
diff --git a/src/value_semantic.cpp b/src/value_semantic.cpp
index dc07a4e..d24a09f 100644
--- a/src/value_semantic.cpp
+++ b/src/value_semantic.cpp
@@ -97,9 +97,9 @@ namespace boost { namespace program_options {
     {
         if (!value_store.empty()) 
             boost::throw_exception(
-                multiple_occurrences("multiple_occurrences"));
+                multiple_occurrences());
         if (new_tokens.size() > 1)
-            boost::throw_exception(multiple_values("multiple_values"));
+            boost::throw_exception(multiple_values());
         value_store = new_tokens.empty() ? std::string("") : new_tokens.front();
     }
 
@@ -139,8 +139,7 @@ namespace boost { namespace program_options {
         else if (s == "off" || s == "no" || s == "0" || s == "false")
             v = any(false);
         else
-            boost::throw_exception(validation_error(
-                                "'" + s + "' doesn't look like a bool value."));
+            boost::throw_exception(validation_error(validation_error::invalid_bool_value, s));
     }
 
     // This is blatant copy-paste. However, templating this will cause a problem,
@@ -162,7 +161,7 @@ namespace boost { namespace program_options {
         else if (s == L"off" || s == L"no" || s == L"0" || s == L"false")
             v = any(false);
         else
-            boost::throw_exception(validation_error("invalid bool value"));
+            boost::throw_exception(validation_error(validation_error::invalid_bool_value));
     }
 #endif
     BOOST_PROGRAM_OPTIONS_DECL 
@@ -188,19 +187,17 @@ namespace boost { namespace program_options {
         {
             if (!value.empty())
                 boost::throw_exception(
-                    multiple_occurrences("multiple_occurrences"));
+                    multiple_occurrences());
         }
     }
 
 
     invalid_option_value::
     invalid_option_value(const std::string& bad_value)
-    : validation_error(string("invalid option value '")
-                       .append(bad_value).append("'"))
+    : validation_error(validation_error::invalid_option_value, bad_value)
     {}
 
 #ifndef BOOST_NO_STD_WSTRING
-
     namespace
     {
         std::string convert_value(const std::wstring& s)
@@ -216,43 +213,111 @@ namespace boost { namespace program_options {
 
     invalid_option_value::
     invalid_option_value(const std::wstring& bad_value)
-    : validation_error(string("invalid option value '")
-                       .append(convert_value(bad_value))
-                       .append("'"))
+    : validation_error(validation_error::invalid_option_value, convert_value(bad_value))
     {}
 #endif
+    const std::string& 
+    unknown_option::get_option_name() const throw()
+    { 
+        return m_option_name; 
+    }
 
-    void multiple_values::set_option_name(const std::string& option_name)
+    const std::string& 
+    ambiguous_option::get_option_name() const throw()
+    { 
+        return m_option_name; 
+    }
+
+    void 
+    multiple_values::set_option_name(const std::string& option_name)
     {
         m_option_name = option_name;
     }
 
-    void multiple_occurrences::set_option_name(const std::string& option_name)
+    const std::string& 
+    multiple_values::get_option_name() const throw()
+    {
+        return m_option_name;
+    }
+    
+    void 
+    multiple_occurrences::set_option_name(const std::string& option_name)
     {
         m_option_name = option_name;
     }
 
-    void validation_error::set_option_name(const std::string& option_name)
+    const std::string& 
+    multiple_occurrences::get_option_name() const throw()
+    {
+        return m_option_name;
+    }
+        
+    validation_error::    
+    validation_error(kind_t kind, 
+                     const std::string& option_value, 
+                     const std::string& option_name)
+     : error("")
+     , m_kind(kind) 
+     , m_option_name(option_name)
+     , m_option_value(option_value)
+     , m_message(error_message(kind))
+    {
+       if (!option_value.empty())
+       {
+          m_message.append(std::string("'") + option_value + std::string("'"));
+       }
+    }
+
+    void 
+    validation_error::set_option_name(const std::string& option_name)
     {
         m_option_name = option_name;
     }
 
-    const char* validation_error::what() const throw()
+    const std::string& 
+    validation_error::get_option_name() const throw()
+    {
+        return m_option_name;
+    }
+
+    std::string 
+    validation_error::error_message(kind_t kind)
+    {
+        // Initially, store the message in 'const char*' variable,
+        // to avoid conversion to std::string in all cases.
+        const char* msg;
+        switch(kind)
+        {
+        case multiple_values_not_allowed:
+            msg = "multiple values not allowed";
+            break;
+        case at_least_one_value_required:
+            msg = "at least one value required";
+            break;
+        case invalid_bool_value:
+            msg = "invalid bool value";
+            break;
+        case invalid_option_value:
+            msg = "invalid option value";
+            break;
+        case invalid_option:
+            msg = "invalid option";
+            break;
+        default:
+            msg = "unknown error";
+        }
+        return msg;
+    }
+
+    const char* 
+    validation_error::what() const throw()
     {
         if (!m_option_name.empty())
         {
             m_message = "in option '" + m_option_name + "': " 
-                + logic_error::what();
-            return m_message.c_str();
-
-        }
-        else
-        {
-            return logic_error::what();
+                + error_message(m_kind);
         }
+        return m_message.c_str();
     }
 
-
-
-
 }}
diff --git a/test/exception_test.cpp b/test/exception_test.cpp
index 33470ea..39de749 100644
--- a/test/exception_test.cpp
+++ b/test/exception_test.cpp
@@ -92,7 +92,7 @@ void test_multiple_occurrences()
    catch (multiple_occurrences& e)
    {
       BOOST_CHECK_EQUAL(e.get_option_name(), "cfgfile");      
-      BOOST_CHECK_EQUAL(string(e.what()), "multiple_occurrences");
+      BOOST_CHECK_EQUAL(string(e.what()), "multiple occurrences");
    }
 }