JQuery :: Modifying ExpCollGroup Function In Share Point 2003

I am trying to modify the ExpCollGroup function within Share Point (2003) and don't have access to server or ows.js file where the function lives. I want the ExpCollGroup function to run (I'm using it to expand/collapse documents in a document library), and then when finished, want to be able to run my own function like DoSomething(). The below code works but fires before the ExpCollGroup code executes. What can I do to make the ExpCollGroup function execute, and then perform my DoSomething function?
$('[id^="img_"]').click(function() {
alert(The Expand/Collapse button was pressed but the loading of documents has not yet begun');})