Private chat all chat

If I am talking to the general crowd or someone ingame beside me I am ok on allchat. If I then send a private message to a player on my friends list then that works ok too.But then I can t get back to allchat where I can talk to the people around me. I have clicked on absolutely everything and can t find a way back to allchat and able to talk to people around me. Please help. What do I have to do to get from private chat to all chat?

I am having this Runescape Gold problem as well as a couple of my friends. The only way we know how to get around it is to make your public chat and private chat boxes separate. Quite annoying. Hope this is fixed soon.