Problem with getting a new Message window from another thread

Hi ,

I'm working on a smart client application. In one of my forms I have a
socket instance which listens for any messages from others and there
are some other windows forms too.

when the sockets recievs any messages it should pop a message about it
even the user is actively working on some other Form other than the
form which has the socket instatnce.(which is handled through a
delegate in the Form)

my problem is when I have a MessageBoz.Show("Message") in the delegate,
to show the incomming message , inworks fine.
But what I need is a customized Message window other than the message
window given by MessageBox.Show();
When I tried to use one of my "MessageWindow" which inherits
Windows.Form the application get stuck..

so What I feel is this is something to do with threading in UI where
trying to update UI from anohter thread. but the MessageBox.Show()
handles it fine.

so I need to implement one of my own MessageWindow Class works like the
MessageBox.Show() with my customized look.

Can anyone give m a clue to start off with this ...

Thanks in advance...

Chathuranga