It always means that you're up against a player who is not really familiar about FL play concepts, regardless of their holding.
In such situation you can be against anything: badly played AA-KK... (a good player will never limp with a strong hand, especially on micro limits) or, maybe, a tilted player who thinks something like: "damn, why do i always get raised when i decide to play... ok... let's rock then".

So, whatever... you can never know against what range you're playing, but you will always know that you're against a weak player.
That's my opinion, of course.