You mean like a constant ammo drain of some sort when a player is wielding the weapon? If yes, then this can be done quite easily.
edit: This is one way to do it.
package something
{
function weaponImage::onMount(%this,%player,%a)
{
parent::onMount(%this,%player,%a);
if(%this.getName() $= "someWeaponImage")
{
//Some code to start leeching
}
}
function weaponImage::onUnMount(%this,%player,%a)
{
if(%this.getName() $= "someWeaponImage")
{
//Some code to stop leeching
}
parent::onUnMount(%this,%player,%a);
}
};
activatePackage(something);