You got me then. David Harris says in that thread that HTML-induced crashes are much rarer now, anyway.

Since I upgraded to the version 4.41, at least once or twice a week Pegasus crashed when I try to delete a message in the new mail folder. There does not seem to be any pattern specifically to why the crash happens or to the email message contents, besides that pretty much all emails I get nowadays are HTML emails.

The crash happens when I try to delete the message in the Preview View. I also updated BearHTML a few times and at times that seemed to have reduced somehow the problem. I run WinXP Pro on a DualCore Intel hardware (2 years old).

Any clues?

I expect you're right in surmising that it's an HTML-induced crash. You could disable the preview pane--see this thread:

Actually the HTML is OK. I say that because sometimes the messages that cause the crash are message we generate on our server and furthermore after restarting Pegasus the same exact message that causes the crash does is previewed just fine and does not cause anymore crashes.