I need a voice chatting script which will allow 2 or more users to voice chat simultaneously. There shd not be any download for the users. They must be able to voice chat on the site itself without having to download anything. Imagine it like the gmail chat. The functions shd be like this :-
1) User logs in to the chat room
2) He selects the users with whom he wants to voice chat
3) The selected users will receive invitations for the voice chat which they can accept or decline
4) The accepted users can start voice chatting with the invited user.
5) The chat room should also provide simple text chat so that the chatters can still communicate if there is a problem with the voice chat.
Important requirement is the voice & text chatting shd work even behind a firewall.
ANY REASONABLE AMOUNT IS ACCEPTABLE.