how to move to the bottom when the frame is resized

Urgently required

I am facing a problem currently.I am a member in the team which is developing a product called "E-INTERACT".It is basically a chat product involving clients and agents.In the client chat page a page with two frames is thrown when he logs in.The top frame is to see the messages that he typed as well as the messages that the agent has sent.top frame is refreshed in regular interval to get the old messages along with the latest messages.Bottom frame is for him to type messages.

The problem is when too many messages are received by the client the top frame size is increased and so a vertical scroll bar appears.When the page is refreshed at regular intervals ,as i mentioned earlier , the client is shown with the frame whose scrollbar is positioned at top.So he has to scroll down to see the latest message of his and the messages of agent.

How to overcome the above mentioned problem ?

I want the scrollbar to be positioned down automatically when the page is refreshed at regular intervals

Kindly help me.
hari


software executive
byzan systems