node-set in .Net 2.0?

Hey

I'm running a node-set heavy transform in .Net, I keep getting the
following error:

The 'Function 'ns:node-set()' has failed.'
If I change the variable that is creating the node-set not to I get
the following error:
The expression passed to this method should result in a NodeSet.

the ns namespace is associated with
xmlns:ns="urn:schemas-microsoft-com:xslt"

IIRC this namespace was allowed in earlier versions of .NET. Does
anyone know if this has changed, has .Net's already arcane nodeset
handling rules changed? Does one have to explicitly allow nodesets to
be created in ones code?

Cheers,
Bryan Rasmussen