Add a "OnClick" javascript event listener on Tabs

How can I add an “OnClick” event listener to tabs?
My tabs are “Blocks” defined in the layout section as “Tabs”.
I need to reload the Tab content each time the user clicks on the Tab.
I noticed that the SC “OnScriptInit” is triggered only when user clicks on an object within the tab. Clicking only on the tab itself does not trigger the “OnScriptInit”.
Thanks a lot.