Well the problem of the comments and code most of the time not appearing in outgoing email, only if the original message was posted via email, is still unsolved. Once in a blue moon it will work with no explanation. No change to anything and it won't work the next time and for many times thereafter. 7 hours is enough. Debugging someone else's PHP on a remote machine with no tools except writing to trace files is just too much. I'll tackle it again some other time.
This morning I did get <tt> blocks in incoming email to show up as [code] blocks in the posted messages, which is really useful.