kingpin, just grab the weapon change event and then set the speed again if its still enabled on that user. The set and get user speed functions I have found to be very buggy in AMX, not sure about AMXx. I did some massive work on shero for AMX to fix some bugs with it.
I found out if you try to set a users speed back to the default it usually mkes them stuck, so I would do that then force them to switch to the knife then back do a last inv
hope that helps
you posted that new attach AS I was posting.... so now maybe my post is useless, maybe not... so w/e