Just use a VM
This implies having a Windows XP licence, which is a bit more than "Just"
Even if these prices are out of date, you get my drift that this is an extra overhead.
I don't think you are allowed to run IE without a windows licence anyway, so the whole idea of running IE in linux would only be for convenience.
Just so you know I have an msdn subscription and therefore legal access to windows, however I would dearly love to ditch this dependency.
Having to test for IE clients is yet another lock in to windows.