Thank you very much for your responses.
Unfortunately the problem remains unresolved. I tried different settings and have installed all Empathy related packages, tried new install of the system but nothing helps.
1. The problem is not related to Firewall, because it does not connect without the firewall turned on.
2. The problem is not related to my Network/proxy settings, because Empathy works great on Mandriva2010 using the same settings.
So, I think the problem is in packaging.
After the Gnome upgrade from 2.26 to 2.28 some package/s got lost and Empathy only works on "old" installs, I mean old installs of Empathy 2.26 (and it's dependence's) and later upgraded to 2.28. But it does not work on New installs of Empathy 2.28 (lacking some "old" dependence's).
I hope the next release of PCLOS Gnome will be with Empathy in default install and will have the all features Voice/Video/File transfer/Remote desktop sharing (the most important for me).
Despite of all above mentioned The PCLinuxOS is the greatest Desktop and the most user friendly distro, I ever tested (I tested many of them) and the first and only Linux distro, I dared and installed on my friends/relatives machines, knowing that they will not have problems with the system.
Thank you Texstar!