[Golimad]

pawn Код:

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
    if(newkeys & KEY_SECONDARY_ATTACK)
    {
             KillTimer( yourtimer[playerid] );
        }
       return 1;
}

// If this function already exists, just hook that timer killer in it ..
// Also Use a SetTimerEx ( Not SetTimer ) ( Timer loop should be false )