fixes for building using visual studio 2010 command prompt
fixes for building using visual studio 2010 command prompt

git-svn-id: e171abefef93db0a74257c7d87d5b6400fe00c1f@4341 f22100f3-aa73-48fe-a4fb-fd497bb32605

antonvw/wxExtension,antonvw/wxExtension,antonvw/wxExtension