Index: build/Jamfile.v2
===================================================================
--- build/Jamfile.v2	(revision 81666)
+++ build/Jamfile.v2	(working copy)
@@ -422,6 +422,10 @@
      <target-os>windows
    ;
 
+alias asm_context_sources
+   : unsupported.cpp
+   ;
+
 explicit asm_context_sources ;
 
 alias select_asm_context_sources
Index: src/unsupported.cpp
===================================================================
--- src/unsupported.cpp	(revision 0)
+++ src/unsupported.cpp	(working copy)
@@ -0,0 +1,7 @@
+
+//          Copyright Oliver Kowalke 2009.
+// 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)
+
+#error "This platform is not currently support by Boost.Context"
\ No newline at end of file