Desactivate "Tap" option in the Joystick Prefab

Hi,

I'm using the Prefab Joystick to control my Avatar. Everything is working fine here.

Here is my question :

Is there a way to de-sactivate the Tap function ? Because, my scene has some objects, with click option. So when I click on an object, the action is ON.Action Example : laod level, load URL, load sound ....

The probleme, is when the josytick is over an object (the jaoystick is made with GUITexture), I can't move I can only lauch the action on the object that is under the GUITexture.

Thanks for your help.