500 Server Errors When Posting Posts

Lately, I seem to have developed a problem with my WordPress 2.1.2 installation: when I try and post something to my blog, the posting eventually happens, though I get a 500 Server Error when it eventually comes back. Unfortunately, my web host doesn’t give me my Apache error logs, so I can’t really see what’s going on. Anyone seen this issue before and have any suggestions how to fix it?