Closing the dialog question.

I want to initiate one closing action if the user clicks a cancel
button or the 'X' and another when it is closed programmatically. I
can easily do this with the cancel button, but am not sure how to
override the 'X' action and if I put it in the 'close' event for the
dialog it always executes even when using javascript to close it. Any
advice would be appreciated, thanks!
Josh Powell