firefox a bit slow on my applet

[dvm]

Hi to everyone, once again. I'm pretty much finished building my test applet. I'm loading quite a few textures (6 24-bit textures 2048x2048 each + 1 32-bit 2048x2048) and render 1000 quads on screen. The program zooms in where the user clicks, zooms out etc.
My problem is that firefox is a bit slow when doing this. I also tested with IE6 and the appletviewer and both gave the same speed. But firefox seems to lag (the animation is not smooth). Does anyone have any ideas why this must be happening? I wouldn't want to give my users a reason to prefer IE over firefox! Thanks