Another Mind-Boggler: Conditional Breakpoint Stops Bug

[jitspoe]

My brain hurts lately. Now I have a new bizarre issue. I have this bug where, occasionally, if you hold the jump button down, you will jump multiple times, even though you're supposed to have to release and press the key again. This is in my Quake2 engine. I'm fairly sure it's related to the way I've decoupled the framerate and network packets, but here's the bizarre thing: when I try to catch it in the act by putting a conditional breakpoint in CL_BaseMove() for cmd->upmove < 200, the issue disappears.

I can type +moveup in the console and watch the character occasionally jump. Enable the breakpoint, and it stops. Disable the breakpoint, random jumping. So weird.

[frag.machine]

Does the bug show in the release version too ?

[jitspoe]