http://bugs.winehq.org/show_bug.cgi?id=10090
--- Comment #4 from Dan Kegel dank@kegel.com 2008-03-07 08:18:17 --- No version. The problem is that wineprefixcreate is trying to use gecko before it's loaded. The message is spurious.
Try this: rm -rf .wine wineprefixcreate
Don't you get the warning?