Well - the security alert is coming from Windows (I would think) - so it's responding to (global?) policy settings here - not quite UAC (User Access Control), but something similar.
You could have a look at that - though if you've not had this in the past, the way I see it there's two possibilities (usually).
A - Someone in your org has tightened the GPO's to be more secure, and Sun hasn't actually changed anything - but now you see this popup because of increased security. It will help finding out "whodunnit" (and specifically - WHAT they've changed) to figure out if this is (1) - necessary - and (2) - how it can/should be worked around/with.
B - Your policies haven't changed, and Sun *DID* change something in the Java installer to comply more with a Microsoft BKM / something or other / thing (it's a technical term, honest).
Based on experience, A is *usually* the more likely option, but that's just a rule of thumb (since you seem so far the only one to bring this up, I feel more confident with suspecting that something in your environment was changed).
If it's the latter, you would have to check with Sun for how they'd recommend the automated installation to work now (they should be working on a BKM I'd hope).
If you're in the "wonderful" position that no one will own up to changing something (or you can't find out otherwise), the way to try and figure this one out will be to see how you can work around this... that could be repackaging the package, with something like our "new" package builder, automating the install with AutoIT / WinBatch or something of the like)...?
Hope this helps you along somewhat .
- Paul Hoffmann
LANDesk EMEA Technical Lead