Why does Android not support UMTS Video calling?

Hi,

When UMTS came out in the UK nearly a decade ago and I got my first video phone, I got really excited and loved it. I then got an iPhone and started to miss the video calling part.

Now I am on Android (a HTC One X), and almost all Androids have a front facing camera, yet none support UMTS video calling. UMTS Video is fast and almast all networks support it, so how comes Android does not?

Sure, we have Skype now, but UMTS video calling is simple, it uses phone numbers and is easy to use and you don't need to register for it. Its also an open standard that any phone and network can implement as its part of the UMTS/GSM stack.

Whats your opinion, why does Android not support UMTS video calling?