i have noticed this peculiar behavior also.

not sure why this is, but i reasoned it away by assuming the manufacturer waits a while after releasing the update, before doing what is necessary to make the update available to the auto-update, cuz once the auto-update goes into effect, there will be relatively *many* folks updating, whereas relatively few with grab the updagtes themselves.

if they get no major complaints (a form of beta testing), then they make the update available for auto-updating.

i'm sure they can control the two different types (manual & auto-updates).

but either way, your observation is common.

Hope you're not delinquent like I sometimes am, as in not updating Ghost 2003 soon enough, and now when I try LiveUpdate, the response is somewhat like you describe, "your Symantec software is up-to-date" or some such, and I KNOW my version of 2003 is NOT the last version.

Checked Downloads at Symantec, and learned that they no longer support 2003.  So, their response to 2003 LiveUpdate SHOULD have been "your Symantec software is as updated as it's gonna ever be."  May not apply to your situation, but thought it might be interesting.