been looking for this
I have literally been trying to find this device for the last 6 months. I am a cisco call center customer, and we have a large set of managers who spend large parts of their days away from their desks. We wanted a non-cell based solution for both voice and email, and this looks like a good fit to me.
The best part is that my attempts at making this work were via sipdroid on android anyway. The iphone was no good for this, and neither was windows mobile.