[TxMt] Annoying switching problem

I've discovered a rather annoying problem when using Textmate with (more than) two projects open, one of which is large. When I cmd-tab to TM the active project appears immediately, but it takes a couple of seconds before the other projects appear behind it. If during this time I alt-tab out into another application, after a couple of seconds (or when I wave the mouse) the other projects will appear in front of the active application, but textmate is not active (ie. when I type it still goes into the other application, but I can't see what's happening because TM is in front of it).

Any fix would be much appreciated!

Hadley