Terminalserver license issue

Dear all,

My Terminalserver has a problem discovering the existing Terminalserver License servers even the Licensing Diagnosis tool discovers everything well.
Environment:

• MS license server with Windows 2008 R2, installed and activated Terminalserver license server, installed 25 TS User CALS for 2008 (and 702 CALS for 2003)
  The License server security group Group Policy setting hasn't been enabled.
• MS license server with Windows 2003, installed and activated Terminalserver license server (Domain license server), installed 702 CALS for 2003
• Terminal server Windows 2008 (plus Citrix XenApp 5 FP2)
• Windows XP SP2 client

Configuration:

• The Terminalserver is configured to use User CALS, the user CALS for 2008 have been applied to the license server.
• The Windows 2008 License server has been specified by configuring License Server discovery mode for the terminal server in the Terminal Services Configuration tool. The Licensing Diagnosis tool reports the server a fine also showing the available Windows 2008 per user CALS. The 2003 server is also reported with the hint of the old version.
• We also added the server as preferred license server in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\TermService\Parameters\LicenseServers.

Issue:

• Logon is only possible with mstsc /admin, otherwise the error "A device attached to the system is not functioning" is shown. After logon a small window on the systray informs the server could not locate a valid license server. But the Licensing Diagnosis tool reports the licensing server correctly.
• After every reboot the terminalserver shows the message: Citrix license error "A problem with Terminal Services functionality has been corrected on the server running XenApp. The correction involves changes to the registry. Please reboot the server."
• If we restart the Terminalservices manually after the reboot everything works fine.

My Questions:
Why can't the terminalserver find the license server even the Licensing Diagnosis tool is able to? Why is the manual restart of the Terminalservices helpful, but not a server restart?

Additional hint:
During installation the Fujitsu ServerView Agents are installed on the Terminalserver, following the below links we uninstalled the agents, after that the discovery works fine in the Licensing Diagnosis tool.
Knowledgebase number KB977686 has been allocated but isn't visible yet.
Links:
http://social.technet.microsoft.com/Forums/en/winserverTS/thread/4fa27bdd-0b9e-440f-a7c7-146a7484a028
http://forum.de.ts.fujitsu.com/forum/viewtopic.php?f=102&;p=132689


Any help is highly appreciated.

Thanks in advance and best regards
Ralf Hoffmann