My advice would be to tell us what the "bug report" says as a start. Then look in the offending application's bug database, if there's a problem you're probably not the first to discover it. If that doesn't work, Google the error message. Once again, you're probably not the first to have the problem. See what you can find on your own.
If you can't figure it out by yourself, tell us:
1. What application you're running (or should we assume Evolution).
2. What you're doing in that application when it crashes.
3. What did you do to your system right before this "bug report" started showing up (not likely that it was "suddenly" if you didn't do something). Did you update your system, install a new package, change configuration settings, hit your computer with a hammer, etc.?
4. What have you tried so far to resolve the problem and what were the results?