Version:           1.8.2 (using KDE 3.4.2 Level "b" , SUSE 9.3 UNSUPPORTED)
Compiler:          gcc version 3.3.5 20050117 (prerelease) (SUSE Linux)
OS:                Linux (i686) release 2.6.11.4-21.9-default

Kmail does not crash and I can't see a common factor that causes the freeze. I ran SuSE 8.2 with Kmail for years on the EXACT same hardware with no issues at all. I upgraded SuSE to 9.3 pro and the versions of KDE/Kmail as shown and the problems started. There are other usability issues but the freeze issue is a show stopper. I have a high speed cable connection that has not been a problem previously. No other applications are exhibiting 'strange' behaviour. I have turned off spamassassain(or tried to anyway) and deleted all the filters associated with spamassassain. I have 7 filter rules. All my folders are very small. My inbox has about 100 messages in it. I am running on a Compaq Deskpro with a 1 Ghz athlon processor and 512 mb memory. Top shows the processor at very high utilization (95-100%) and Kmail is the process driving that utilization. I have tried changing the mail update time from 10 minutes to 2 minutes and other variations but that has no effect. I never get more than 6 messages new on an update. The service is POP, the provider does not use IMAP. The delay, which means Kmail is frozen, lasts from between  5 and 10 seconds. I can catalyze the problem by just clicking around in Kmail, by that I mean click on the trash folder, then go to the inbox and open a note, then go to compose, then jump back to the junk folder, Just moving around in Kmail. After between say 7-15 'moves or keystrokes or mouse clicks' Kmail freezes for some period of time, you can't do anything in Kmail at all although everything else seems to work fine, after which it comes back to life. Also, it queues keystrokes while its frozen so if you've typed a line in a compose message when it un-freezes it'll finish the line you typed...does that for delete messages too Dooooooohhhhhh :( I've tried shutting everything down but Kmail to see if that made a difference but it didn't. The machine is almost never highly utilized regarding the processor. I've been trying to figure this out for a while and its clearly way over my head. Good Luck, I've used Kmail for years and I would sure like to continue to use it.
Joel