Creating a gleam

Anyone know how to produce an effect similar to the shine/gleam that occurs when you run your mouse over the Ultrashock logo at ultrashock.com ? I pretty sure it's done with a mask, but I just can't get anything I attempt to pull off to work right.

If you want to see what I'm trying to gloss up, head on over to caseypeicott.com and look at the yellow "Buy New Homes" button. I'm trying to create a subtle shine effect traveling across it every few seconds, to draw attention to the button, but producing an Ultrashock-like effect has thrown me for a loop! Any suggestions? Thanks,

hello,

I have a gleam sample button you can see here:

http://laurencewillis.com/dev/gleam.html

the fla file is here:

http://laurencewillis.com/dev/gleam.zip

hope that helps