Is Samsung HDTV UE48H6400AK overclockable?

[okrongly]

Hello Forum!
I've spent 2 days searching and experimenting with this 3d TV.
Couldn't get working anything better than 60Hz on every resolution.
Google said that TV is 100Hz/120Hz so it should be capable to get at least 100Hz.
Some people says that Samsung blocks higher refresh rates through HDMI. Is that true?
Anybody have luck with H6400 series?
Best regards,
Michael