Teleport by single touch - How to ?

Hi All ! I need to create a teleport, but instead ppls use the second mouse button on the teleport and choose the "sittext", a simple touch should teleport the agent.Bellow my code.It's works, but using the sit method.What should I do to perform my needs ? ty !

default
{
state_entry()
{
vector target = <137,84,25>;
rotation my_rot=llGetRot();
llSitTarget((target - llGetPos()) / my_rot,ZERO_ROTATION / my_rot);
llSetSitText("Teleport";




}
touch_start(integer total_number)
{


}
changed(integer change)
{
if(change & CHANGED_LINK)
{
key id = llAvatarOnSitTarget();
if(id != NULL_KEY)
{
//llSleep(0.1);

llUnSit(id);
}
}
}

}

edit the object, and on the bottom of the General Tab of the edit menu, will be a section that says:

"When Left-Clicked:"

And has choices. Choose "Sit on Object".

Then just by clicking once, they will be seated on the teleporter, and be whisked off to their destination.

Thanx a Lot !