Its actually:
function weaponImage::onCollision(%this, %obj, %col, %fade, %pos, %norm)
{
if(%col.getClassName() $= "Player")
{
%col.setTempColor("1 1 1 1",ammountOfTimeHereInMS);
}
}
Ammount of time is the length of time you want them to stay that color. If you want them to be permanent, either set it to a very high number, or make a script to loop through all the player nodes and set them to white.