Limp re-raise with pocket pair

[speirs]

I was thinking about this scenario that doesn't come up very often but still: Is this a play or just crazy? I play $2-$4 limit.

Say you open-limp with a pocket pair like 77 or 88 or maybe even 99, which you will open-raise more often than not, but for the sake of discussion, you limp.

Now one or two people also limp and the big blind raises. He can do this with a range of hands, not all being monsters like AA and KK but also QQ JJ TT AK AQ AJ AT KQ KJ suited or not. The first half have you dominated, the second not. You open-limped. Do you

1. Just call?
2. Raise, trying to isolate?
3. Is this question totally stupid to begin with and/or will the limpers call anyway?
4. Other...

Does it matter

1. What pocket pair you have? How high/how low?
2. How many limped?
3. If the small blind completed?
4. Other...