I recently signed up with Comcast (Central NJ area) HD channels including HBO and to my surprise found that there is no HD movies listed under HBO -OnDemand . ALl other movie channels have got HD-movies under on-Demand. When I called up the Comcast, they said that the HBO network is the one responsible for all the programs under On-Demand section and they have no control over it. Is that true?

All I have are some Sopranos ep's on my system.

Count your blessings. Cox OKC's OnDemand service has NO HD shows.

HBO determines which programs/movies will be made available via On Demand for HBO. Comcast can provide fewer choices than that, but they cannot unilaterally require that HBO provide anything for On Demand if HBO doesn't wish to do so.