Share module and "Code to execute on-click field"

Hello,

I want to track what users are sharing with "Share Module" (which allows to send links to nodes by mail, post to Del.icio.us,...

The last field of the settings form says "code to execute on click". Well, I don't know which click it is (the one of displaying the gadget or the one of submitting any of the options) but I trying to find how to use it.

As I did not find aany documentation I am trying to do something really simple, like the code below (it works in any body field with PHP filter:

But it did not seem to work at all, the page reload when I push the "Share" icon.

Does anybody has any clue on how to use this filed or on how to track what users are sending away with the "Share module".

Many thanks for any help,

Ramón