For the N900, the ioquake3 package uses OpenGL ES rendering, which is directly hardware supported in the Cortex A8 processor in the phone:

http://www.arm.com/products/processo.../cortex-a8.php


I'm not sure why you think it's using SW emulation for the rendering. Do you somehow have an N900 without a Cortex A8 CPU? Did you passs a special flag to the binary to force SW rendering?

If your FPS are low in the game, it much more likely due to available system resources.

How many applications do you have running in the background?

How many daemons do you have running?

How many widgets do you have running on your desktops?

How much RAM is available for the game to use?

Do you have the game data files on an SD card with a very low I/O rate?