In Finland I've had nothing but very lenient experiences with getting my Nokia phones fixed by Nokia care.

My N900 USB broke, got an entirely new N900. My 5800XM touchpanel broke, they fixed it. My earpiece in my N900 broke 2 times and 3 times on my 5800XM. All fixed with no other questions asked besides if my devices were in warranty.

Edit: And about the 90-day warranty: I've heard of no such thing, and can say for a fact that such a warranty doesn't exist for Nokia devices at least in Finland. That must be a very regional thing.