I install yahoo messenger for android V1.8.3.13903 and Also video and voice plugin V1.6.0
It's Connect to yahoo and I can do text chat but when I call voice or video for my yahoo friend,it shows call is in progress but they don't hear any thing and Also when they call me with voice or video,me too don't hear or view any thing and at the end it reports my friend don't answer me
My phone is Sony Ericsson XPERIA RAY and I upgraded android to 4.0.4

thanks