I have just got a Wyse Xentih and Xenith Pro to test with our XenApp 6.5 environment. I have set up the DHCP option tags for 161, 181, and 182 and everything seems to be running nicely.
However I do have an issue with a Scanner (CanoScan Lide 100), when I plug the scanner in and check the Event Viewer on the Xenith it says it is detected and redirected yet when I try to scan something in using Windows Fax and Scan as I would normally it says it cant find a scanner.
To get a scanner running against a XA server, you will need TWAIN redirection. To use TWAIN redirection you need to install the TWAIN drivers locally and obviously this is not possible on Xenith. Therefore the TWAIN redirection feature is not available on Xenith.
With XD it will work as the scanner is mapped via USB redirection in the session.