As you can see in the attached bug report, it seems to be a bug when quitting evolution with unfinished messages that crashes the program, but since Ubuntu 10.04 doesn't provide Bug Buddy, the user doesn't notice that the program crashed.
In order to be able to check this I had to download the latest stable releases from Mandriva and openSUSE and run them live.
As you can see in the attached bug report, it seems to be a bug when quitting evolution with unfinished messages that crashes the program, but since Ubuntu 10.04 doesn't provide Bug Buddy, the user doesn't notice that the program crashed.
In order to be able to check this I had to download the latest stable releases from Mandriva and openSUSE and run them live.
I hope it helps,
Pablo