I was thinking of pushing the lookup off into a thread and go do something else

If by chance that something else would be... yet another DNS lookup, you might be better off using a POE::Component::Client::DNS object and perform many lookups in parallel. This can be a big win, provided you don't particularly care in which order the results come back. That is, if you ask for A, B, C, you might get the results back in the order B, C, A (but in general this is not a problem).

There's a recipe in the POE cookbook that can help you get started.