[JDEV] urgent: Proxy Server

[chandan sonaye]

Hi,
      I am working on a Internet based project .
      In this, we are developing a Instant Messaging client using
Jabber.
      Our Jabber server will be installed on our site.
      We want that our client who is behind the firewall (proxy server)
should connect to jabber server.
      How can my client connect to Jabber server through the proxy
server ?
      Can you please tell me how to overcome proxy server ?

     Thanks,

     chandan