Symantec have issued an advisory that the virus definition dates on its Symantec Endpoint Protection software (version 11.x, or 12.x for the Small Business edition) are incorrectly reporting the virus definition dates for any period after Dec 31, 2009.
This glitch can be confusing to users who suspect their definitions are out of date, and are justifiably concerned. However, for the moment there is actually no risk.
In brief, the program has a bug that disallows it from installing updates dated in 2010; to temporarily get around this, Symantec have dated all their updates since Dec 31, 2009 as Dec 31, 2009. Instead of showing a more recent (accurate) date, they have just been incrementing the Revision number.
As of Jan 3, 2010, the latest revision number was "rev 114".
Symantec are working on a more permanent fix for the program, but for the moment, users need not be concerned. In the meantime, if you have questions on the status of your SEP, please contact us for more information, or have a look at Symantec's knowledge base article on this subject here.
As of this date, this problem seems to have been resolved. Symantec have created a patch, and it should automatically be installed each time LiveUpdate runs. It also appears to be installed when running a manual update directly from Symantec's site (usually done only by Administrators, and only if LiveUpdate is not available for some reason).
Unless your signature dates are showing as Dec 31, 2009 still, no further action should be required.
If you have further questions on this, please contact us.