using different refresh rates/modelines for different games?

[jimhend~1]

hi
i have these 2 modelines in my xorg.conf
ModeLine "800x600_125.00" 89.6 800 840 1040 1120 600 602 614 640
Modeline "800x600_144.00" 97.32 800 856 936 1056 600 601 604 640

the 125Hz mode i like to use for quake3,
and the 144Hz mode i like to use for fuhquake (quakeworld)

to juggle between the 2 different modelines i am commenting/uncommenting the modeline i want and restarting X.
is there an easier way to force a game to the non-default modeline?

i tried xrandr , but when i load quakeworld the game seems to override xrandr and revert to the default modeline.
any help appreciated.
TIA