Can I use DataSets or DataTables with WCF?

I've just getting started at using WCF, but like what I've seen so far.* I've been reading about it, writing my interfaces and implementing them with classes, etc.* It seems to be going well.

But one thing I would like to do is both pass into methods ADO.NET DataTables or DataSets.* I know that isn't the "proper" way to do things, especially if you want to be cross platform.* But in this case I am writing WCF services which will be used in-house, probably using TCP for the protocol, between our Windows 2003 Servers and the clients' PCs.* In that situation, is it OK to use DataSets and DataTables?* Or doesn't that work?