"Loading mask" in ui.tabs

"Loading mask" in ui.tabs

Hi,
I would like to prevent users from clicking on tab content when it's
asynchronously loading content when a tab has been clicked and display
a loading screen where the tab-panel is normally displayed.
I was unable to find such functionality on the ui.tabs widget. Then I
went to see if I could get a hold of the panel that was displayed
while the clicked tab was loading. I found out that I *can* get a hold
of the panel of the clicked tab, but that isn't displayed until it has
finished loading.
Lastly I tried to jQuery.extend the ui.tabs.prototype, but
unfortunately I got in trouble when trying to override the load method
and trying to call it on it's superclass, because it caused the "too
much recursion" error.
So I am at the end of my options and hope someone can point me in the
right direction.
Best,
Dirk Louwers
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