Got SKYPE Hack version 2.0 from from xda-developer forum here : http://forum.xda-developers.com/showthread.php?t=1148271 ....
Then test on my Samsung Galaxy S2 (on 3G) video call with iphone 4 (on wifi)... Video smooth and sound is great... Both front and back camera worked.
Non hack version 188.8.131.52 updated from marketplace.
Here HD video of SKYPE video call between Samsung Galaxy S2 and iPhone 4