Once again, when you use the /S modifier in regex, it'll only strip the values filled in $regml()
The only thing that gets stripped is the trigger, not $2-, as per froggie's example.
What DJ_Sol has provided will suffice. I've always though it's a safe bet to include the $strip() or tokenize 32 $strip($1-), saving yourself some trouble if any trigger is rendered unresponsive, while you don't have your mIRC set to strip messages.