Citrix XPa Published Apps.

Hello!

ive got Citrix XPa running on server 2000 and i have a published app on it. When i try to connect to the app from the client i just get the bluw windows backgroud as if its trying to log in and nothing else happens, though if i log directly onto the server as the same user it logs on fine and i can run the app!!?!?

any ideas! help!