david hayden blogged a while ago about bugs in the validation block (using policy injection). i.e. not being able to use interfaces. also that patch was being brought out, has this patch been created or do we still need to extend MarshalByRef to use Validation
with the PolicyInjection Block.
The bug was fixed in Enterprise Library 3.1.
You can probably find a screencast or sample download on
PnPGuidance.net if you are interested. Try:
Day of Patterns and Practices - Tampa Roadshow May 25, 2007 : Enterprise Library 3.1
one of the Enterprise Library Screencasts for a walkthrough.
Either way, it was definitely fixed.
Hope this helps.
Microsoft MVP C#