What's with WPF Data Validation?

Why did I have to spend so long at work last week replicating Silverlight's input validation template behaviour in WPF? Surely I'd have been able to find this work done by someone else? Maybe they're like me and can't really post what they've done for public use.

Don't see how you can write a decent WPF LOB application though without creating some half decent input validation templates.... They must be out there somewhere. Maybe my google skills aren't as good as I thought....