Send a webcam stream to multicast address

[marika82_A]

Hi,
I'm tring to send multicast webcam stream but the receivers don't receive null.
I've compiled VLC with ./configure --enable v4l .
On side of the server vlc gives me many errors such as :
"cannot create packetizer output, demux error...";
On side of the clients I don't see anything!

Do somebody tell me what is the problem?
Does VLC needs of some particular library?
Please help me!