Supported HP printer devices on Terminal services and Citrix
On this link you can find HP LaserJet printers and supported driver versions for Citrix. Terminal services are also supported but they are not mentioned in this list because Citrix runs on top of Terminal services.
PDF is available at http://h71028.www7.hp.com/ERC/downloads/4AA0-8465ENW.pdf
List has been update April 2008 so it is pretty fresh list of HP devices that will work on Server based computing environment.