http://bugs.winehq.org/show_bug.cgi?id=27371
--- Comment #4 from fracting fracting@gmail.com 2011-06-03 09:26:14 CDT --- Created an attachment (id=35004) --> (http://bugs.winehq.org/attachment.cgi?id=35004) trace:+warn,+heap
Maybe req->netconn is NULL... maybe this is a use-after-free. What happens if you run with WINEDEBUG=warn+heap ?
Does this help?