No. GPS derived coordinates obtained remotely can only be sent if you allow the trigger to occur, or you've installed a 3rd party application to do the same. On its own, straight out of the box, the N900 (and I'm pretty confident every other Phone made by Nokia) cannot.

In the case of calling emergency numbers, I'm not sure what happens on the N900 - generally speaking the carrier has an obligation to forward the location to the emergency service, it's not usually done by the phone itself.