http://bugs.winehq.org/show_bug.cgi?id=16466
--- Comment #19 from Mikolaj Zalewski mikolaj.zalewski@gmail.com 2009-01-18 12:50:16 --- Created an attachment (id=18800) --> (http://bugs.winehq.org/attachment.cgi?id=18800) testcase
I've found it surprising that NULL is a callback item, so I also wrote a test that shows that. If you would like to use it, I attach it.