Subject: Where did all the solar system's water come from?

I have read theories of the origins of Earth's oceans and one seems to be 
more prevailent than others, earth's oceans came from cometary impacts 
during the early dynamic solar system, this seems to not hold very well.  
It would take a lot of comets to create the volumes of water that is the 
Earth's hydrosphere.  Also if the earth 'caught' it's water that way, then 
why don't all the planets have considerable amounts of water proportional 
to their size and location in the system?  
Also, how did all the water in the solar system come into being in the 
first place? Was it there before the sun formed?
Thank you for your time.
-Matt

Re: Where did all the solar system's water come from?