diff --git a/src/build/toolset.py b/src/build/toolset.py
index 672d18f5a..59ddd7378 100644
--- a/src/build/toolset.py
+++ b/src/build/toolset.py
@@ -9,6 +9,7 @@
 
 """ Support for toolset definition.
 """
+import sys
 
 import feature, property, generators, property_set
 import b2.util.set
@@ -23,6 +24,7 @@ __re_split_last_segment = re.compile (r'^(.+)\.([^\.])*')
 __re_two_ampersands = re.compile ('(&&)')
 __re_first_segment = re.compile ('([^.]*).*')
 __re_first_group = re.compile (r'[^.]*\.(.*)')
+_ignore_toolset_requirements = '--ignore-toolset-requirements' not in sys.argv
 
 # Flag is a mechanism to set a value
 # A single toolset flag. Specifies that when certain
@@ -393,10 +395,9 @@ def add_requirements(requirements):
     be conditional or indirect conditional."""
     assert is_iterable_typed(requirements, basestring)
 
-    #if ! $(.ignore-requirements)
-    #{
-    __requirements.extend(requirements)
-    #}
+    if _ignore_toolset_requirements:
+        __requirements.extend(requirements)
+
 
 # Make toolset 'toolset', defined in a module of the same name,
 # inherit from 'base'
diff --git a/src/build_system.py b/src/build_system.py
index b5a3b2775..9d7e0d395 100644
--- a/src/build_system.py
+++ b/src/build_system.py
@@ -8,6 +8,15 @@
 # Distributed under the Boost Software License, Version 1.0.
 # (See accompanying file LICENSE_1_0.txt or copy at
 # http://www.boost.org/LICENSE_1_0.txt)
+import os
+import sys
+import re
+
+import bjam
+
+# set this early on since some of the following modules
+# require looking at the sys.argv
+sys.argv = bjam.variable("ARGV")
 
 
 from b2.build.engine import Engine
@@ -16,13 +25,11 @@ from b2.util.path import glob
 from b2.build import feature, property_set
 import b2.build.virtual_target
 from b2.build.targets import ProjectTarget
-from b2.util.sequence import unique
 import b2.build.build_request
 from b2.build.errors import ExceptionWithUserContext
 import b2.tools.common
 from b2.build.toolset import using
 
-import b2.build.project as project
 import b2.build.virtual_target as virtual_target
 import b2.build.build_request as build_request
 
@@ -32,13 +39,6 @@ from b2.manager import get_manager
 from b2.util import cached
 from b2.util import option
 
-
-import bjam
-
-import os
-import sys
-import re
-
 ################################################################################
 #
 # Module global data.
@@ -421,8 +421,6 @@ def should_clean_project(project):
 
 def main():
 
-    sys.argv = bjam.variable("ARGV")
-
     # FIXME: document this option.
     if "--profiling" in sys.argv:
         import cProfile