Hide an application's dock icon [duplicate]
Possible Duplicate:
Show/Hide Application Icon in Dock
Is there any way to keep an application from displaying an icon in the dock on Mac OS X?
Only the way mentioned in the linked topic, i.e. you will lose your application menu and the entry in the Cmd-Tab application switcher. The behavior is similar to all applications that allow you to do this via a preference, you never get a menu without a Dock icon.