Bouncing icon in the dock

When I have a panel attached to my window, the dock icon bounces up and down. I’m quite happy to have a bouncing icon when a dialog or alert is displayed unnattached to the window, but I used the attached panel to show progress, which doesn’t really need the user to be ‘notified’ by the bouncing icon.

Does anybody know a way of stopping the icon bouncing, or preventing it bouncing in the first place?

Thanks in advance,
Nige