diff --git a/test/deduced_unmatched_arg.cpp b/test/deduced_unmatched_arg.cpp
new file mode 100755
index 0000000..c4f35a0
--- /dev/null
+++ b/test/deduced_unmatched_arg.cpp
@@ -0,0 +1,25 @@
+// Copyright Daniel Wallin 2006. Use, modification and distribution is
+// subject to 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)
+
+#include <boost/parameter/parameters.hpp>
+#include <boost/parameter/name.hpp>
+
+namespace parameter = boost::parameter;
+namespace mpl = boost::mpl;
+
+BOOST_PARAMETER_NAME(x)
+
+int main()
+{
+    using namespace parameter;
+    using boost::is_convertible;
+    using mpl::_;
+
+    parameters<
+        optional<
+            deduced<tag::x>, is_convertible<_,int>
+        >
+    >()("foo");
+}
+