IM HAVING MAIL PROBLEMS TOO but on my girlfriends iBook. i had them on my eMac too, and im 99% sure its do with a httpmail plug-in i had for hotmail. i managed to completely get rid of it on my machine cos i did a clean install, but then i got the panther version again to see if itd work but it doesnt, so dont even try it. i had the same problem, comm-Q wouldnt quit it, i had to force quit. also, when i clicked the dock icon it no longer popped up, i had to go to Window > Message Viewer.
im having problems on the iBook tho, which wasnt a clean install. i got the new httpmail 1.43 version, but aha! think ive just cracked it! so..
For those with Hotmail Mail problems:
If u did a clean install, DONT install the panther 1.43 version of httpmail, it doesnt work.
If uve already done that or didnt do a clean install, get the 1.43 version and install it. Reboot. Launch Mail, and go to preferences, then make the window bigger in accounts and u'll see the httpmail logo on the right. Control-click and remove it, then quit mail (maybe a force quit will do the trick). then spotlight 'httpmail' and delete all of them (anyone else think u should be apple to comm-backspace things from the spotlight menu instead of physically dragging them to the trash? anyway..), think theres about 10 folders and other various things. then Reboot, and it should be fine. Basically, try to get rid of EVERYTHING to do with httpMail.
nice