OK, have to ask. Why do you want to change it?
If you specifically want to use a particular server you could try setting up actions that manually map to the required server rather than using the inbuilt ones that assume the use of the preferred server.
If the issue is that the auto-selection is incorrect, have you looked at the IP address range setting in the preferred server definitions so that machines on a particular subnet would use that one over all others?
Mark McGinn
MarXtar Ltd/MarXtar Corporation
http://landeskone.marxtar.co.uk
LANDESK One Development Partner
The One-Stop Shop for LANDESK Enhancements