Comment 7 for bug 448285

Well, I'm sure that in 0.46 in both linux and win32 stderr appears in a dialog. I'm also sure that inkex.errmsg() dumps to stderr w/newlines (which is kinda funny, since I defined the same function in my extension for debugging).

If you need me to confirm this in SVN I will, but it may take some time b/c I do not have win32 set up to build anything.