CHINAL - 2009-05-27

I did a short movie with a Nokia 2760 cellphone and the extention is "3gp" and I couldn´t open it with Windows Midia Player. Than I dawnloaded the XP Codec Pack 2.4.7 with the Midia Player Clasic 6.4.9.1.
Now, both can open the video but both has no sound.
How can I configure MPC to do it? Or WM Player? There is another codec to download or only configs?
Thanks in advance.
CHINAL