The Contact Details webpart does not display the user's presense- the indicator is greyed out. However, the Site Users webpart will display the user's presense. Is there a parameter I am missing?

Could you please let me know which version of SharePoint are you using? In MOSS 2007, the Site User web part does not track user presence. The Contact Details web part will. For the track user presence feature to work, you should have office communicator installed. For detail, please read http://technet.microsoft.com/en-us/library/cc262338(office.12).aspx#section4

We are using WSS 3.0 in the BPOS environment. In response to your comment, the Site User web part is showing presense, but the Contact Details does not in my environment.

It seems to work if I add the Contact Picture (and the user has one) as an option. However, it only works temporarily after I update the webpart. Any screen refresh, it goes back to grey indicator.