After I run a wine program (eg notepad.exe), sometimes I don't get my login screen after I log out. It goes back to the screen that showed just before X started up, and just sits there. I can switch to tty6 and login (so it's not frozen), but obviously something's wrong. Here's what's in .xsession-errors:

--------------
xset: bad font path element (#76), possible causes are:
Directory does not exist or has wrong permissions
Directory missing fonts.dir
Incorrect font server address or syntax
xset: bad font path element (#76), possible causes are:
Directory does not exist or has wrong permissions
Directory missing fonts.dir
Incorrect font server address or syntax
startkde: Starting up...
kbuildsycoca running...
QFont::setPointSize: Point size <= 0 (-3)
kdecore (KAction): WARNING: KAction::insertKAccel( kaccel = 0x80920d0 ): KAccel object already contains an action name "play_pause"
QLayout "unnamed" added to QVBox "unnamed", which already has a layout
kdecore (KAction): WARNING: KAction::insertKAccel( kaccel = 0x80920d0 ): KAccel object already contains an action name "play_pause"
QLayout: Adding KToolBar/mainToolBar (child of QVBox/unnamed) to layout for PlaylistWindow/PlaylistWindow
QPainter::begin: Cannot paint null pixmap
STARTUP
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 19
Minor opcode: 0
Resource id: 0x2800001
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 19
Minor opcode: 0
Resource id: 0x2400005
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 7
Minor opcode: 0
Resource id: 0x18000dc
X Error: BadWindow (invalid Window parameter) 3
Major opcode: 6
Minor opcode: 0
Resource id: 0x18000dc
QObject::disconnect: Unexpected null parameter
QObject::connect: Cannot connect (null)::activePartChanged( KParts::Part * ) to KHTMLPart::slotActiveFrameChanged( KParts::Part * )
startkde: Shutting down...
klauncher: Exiting on signal 1
KWrited - Listening on Device /dev/pts/0
startkde: Running shutdown scripts...
startkde: Done.
----------------

It's interesting that nothing happens until I actually log out (ie everything works until then), and it's not consistent (one time I ran notepad and was able to logout).

Any thoughts on what the problem could be? I don't know if it's wine, or wine+kde, or my X setup, or what. If anyone has any ideas on what the problem could be, or where I could look for more error messages, or where I could get more information, I would really appreciate it.

I had some bizarre stuff happening after running wine also on SLackware. It made me uncomfortable enough to remove wine completely. The programs I ran under wine actually worked fine for the most part, but, after exiting wine, stuff was funky -- Hard drive acting weird, CDROM not responding, and weird video issues.
I got rid of it and everything's been fine since.
I can't say for certain that your problems are wine related, but... Wine is a beta. And really, you *are* putting a touch if Windows into the machine and if a touch of Windows is anything like a touch of Flu, then.. Your machine probably doesn't like it much

Please don't tell me you're using wine to run notepad. (that would be both hilarious and sad)

Indeed, wine has many many issues. Don't run it unless you absolutely have to, or you play Window$ games.

Sorry, I guess it does sound like that. No, I'm not running wine just for notepad. I'm simply using notepad as an example of the problems I'm having with other programs - it's easier to just run notepad, which everyone else also has if they use wine.

Hmm. Well, Wine's a great idea, despite its purpose but depending what exactly you are intending to use it for, there are likely linux variants/replacements for the same type software -- with the exception of most games.
It is a kinda dangerous idea, atleast as a beta for sure. Though I read an interesting article somewhere the other day, where a guy tried to run a half-dozen Windows viruses under Wine, to test Wine's actual 'exactness' of how well it emulated the Windows environment... None of the viruses would run.

That's true. The programs for Linux are coming along, but it would be nice to be able to run/test Windows programs without my computer crashing.

So it sounds like there aren't any suggestions as to how to fix the error?

Well. Probably not much that will help you.. Wine is a HUGE application, it's a BETA, and is likely quite buggy. Not many people around here are likely trying to debug it. But never hurts to search the forums with the SEARCH function. Just Search for 'Wine' and you'll get every thread there is m,aybe someone else has crossed this bridge already.
I don't think the Wine Development crew even wants/allows support requests until it's out of BETA stage, but the Wine site may have a) a forum, or b) a bug-submission area.
I kinda get the impression it's something of a "use at your own risk, best of luck, hope it works" type of situation.
Besides, Wine is not a very good testbed for (making) Windows programs. There are other methods of doing teh same thing, though ultimately, nothing will proof a Windows program like an actual Windows machine (though I see your point -- Wine is less likely to hang a machine than Windows is)..

Actually, wine (Wine Is Not an Emulator) ... technically it's just a port of Window$ APIs.