I did a quick google search for a de-thump circuit (since that's really what you are looking for here) and found this really simple circuit. Sure it needs adapting to your needs but relatively speaking it's much less complex than the 555 timer curcuit.

I could have sworn the schematic for such a circuit was once posted ont this BBS, but I can't find it in a search.

Possibly John (who owns the site) posted something on this BBS, if you scroll down on that previous link you will see he's an empeg owner, it's a small world

Edit: <teaching grandmother how to suck eggs> This thread is perhaps the one you were thinking of?.</teaching grandmother how to suck eggs>