How do I get a SONY HX800 to play 3D side-by-side through an HDMI port?

The SONY happily plays 3D files from Blue Ray and a 3D camera but it wont let me change into half sbs mode when connected via one of the HDMI ports.
Is this a serious limitation of the Sonys or is there a way to set this up?
Any guidance would be appreciated.

 

An answer

It seem that not all video out boxes are created equal. PVRs etc must be "3D compatible" on their HDMI port to communicate with a 3D TV. I now have such a PVR (STRONG SRT 5430) and I can send 3D videos (half sbs, over/under) to the TV and watch them with my shutter glasses in 3D HD. Problem solved. Anyone want a dud 2D PVR?

 

It is not obvious...

But when the side by side video is playing (You can see two pictures) press the options button, select the 3d menu, turn on 3d, then pick side by side.

 

For the HX800, just play the video using any input, then when you can see two images side by side on the screen, hit the 3D button on the remote, then hit Options -> 3D Menu and change the 3D Mode to Side-By-Side.
If you have your TV plugged into your player via HDMI you may find that the "Options" button will bring up the options of your player instead of your TV. Hit the "Sync Menu" on the remote, then go to TV Controls and click Options to bring up the TV options.
Then follow the steps above to switch to SBS.
I successfully played the Lion King SBS 3D on my 55HX800 with Samsung 3D Bluray player playing from my external HDD plugged in via USB last night using this method.