Qualified names in TH?

I'm trying to write some Template Haskell code that (among other things) manipulates IntSets. So, for example, I'd like a splice to generate a call to Data.IntSet.fromList. However, I'm not sure how IntSet will be imported in the target module. Is there a way to resolve the fully qualified name (or similar) to a TH Name, without having to know how it's imported in the splicing module? (The obvious approach---mkName "Data.IntSet.fromList"---seems not to work in GHC 7.8.) Thanks! /g -- The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336.