As far as I got of your post, it seems you have three issues:
1- The update date goes no later than 31 Dec 2009
2- The live update does not function properly
3- The Clients do not receive the updates
Solutions:
1- This is a known issue after the 31st Dec 2009 afterward. But if you cast a look on the revision, it is being increased which is the current solution that Symantec is using. Means the clients and server have the latest updates despite the date is not up to date. Don’t worry, it will be solved ASAP
2- If you are sure that the live update is not functional, one of the best solutions is the following steps:
a. Uninstall the Liveupdate
b. Restart
c. Install the liveupdate again
d. Go to the folder where Symantec Endpoint Protection is installed, in the “bin” folder run the Lucatalog.exe twice: first time with switch “-cleanup”, and the second time with “-update” (Lucatalog -cleanup, Lucatalog -update)
e. Run the Luall.exe to retrieve the latest updates.
3- If the clients do not receive the updates from server, there are several reasons. I advice do a research on the subject in the forum or raise another ticket.