http://bugs.winehq.org/show_bug.cgi?id=23145
--- Comment #11 from A Wine user RandomAccountName@mail.com 2010-10-08 09:55:43 CDT --- Hi,
This appears to be fixed. Opera 10.53 starts up successfully with Windows version set to Vista in git (wine-1.3.4-202-g47d2a00). I also tested it in 1.2-rc3 and can confirm that it didn't work in Vista mode at that time.