Click on 'Manual', you get a ugly Xaw dialog that says: 'Unable to execute mozilla. Online help is not available'. The mail one as a tooltip has 'Mozilla -mail -splash' tooltip. Neither of the mozilla icons, nor the xmms icon, appear to launch anything.
it looks like, mozilla and xmms are not installed on your machine!
But, they are. Odd. Updated to todays tree and they now work, though. (except for xmms, different bug.)