is it possable to make a web-based chat useing php?

is it possable to make a web-based chat? if so how would I do it. if not what do I use?I am kinda limited to php . if it is possable then what will I need to get started and where do I start. I know a little php ... anything I need I will learn. the concept I have is that something will allow client side to communicate with client side. and also client to server. if you could give me any info I would be really happy. I don't wanna have to use java or flash or anything like that. if it can't be done in just php alone then I will do it another way but I would really like to keep it to php...but I don't have to

thanx . mike

client to client with PHP ? I don't think that is possible. PHP is serversided so it will be at least client-server, where all clients get the same info.
you could simulate something like a chatbox, by having the client reload the pages (with javascript for instance) with a really short interval, but this will be a bandwith eater.
Without auto-reload, the clients will need to constantly refresh the pages

I think you need to look into IRC-channels and maybe wrap some PHP around it. You migth want to check out :
http://phpclasses.moveit.be/browse.html/package/1309.html