Flash behaviors duration?

Is there a way to set the flash behaviors duration time of a player sprite to be indefinite until it collides with another player sprite?

Iv been playing around with the objects expressions, and searched the forums with no success.

Any help would be greatly appreciated.

Just in case anyone is interested I figured out a little walk around for this.

All I did was set the flash behaviors duration time to a very high number of seconds much more than will be needed for this game that I'm developing. Then I set the player 1 sprite to stop flashing on collision with the player 2 sprite.

I was just hoping that there might have been some sort of expressions I could have used instead to create this effect.