Tunneling X through telnet and ssh (at the same time)

[le_random]

I'm looking for some advice...

Is it possible to tunnel X-clients through the following sequence?

Old SunOS server    ----->   Fedora Box              ----->  Windows box
(Running X Client)  ----->  (Running Window Manager  -----> (Running X Server)
                      |     and X Clients)             |
                      |                                |
   connect through Telnet                           Tunnel through SSH

I have no administrative access to the SunOS box, and no admin access to the Windows box, but full root access to the Fedora box.
The reason is I would like to be able to view data from X-apps held on the SunOS server, without having to close down my connection (and therefore all my apps) on Fedora.

Is this possible, or am I asking too much?

Many thanks in advance,

Tim

PS. I can already connect to the SunOS box straight from Windows using Exceed and XDM, and from the Windows box to Fedora using Exceed/puTTY.
I have limited access to Exceed's configuration.

PPS. Please don't educate me on the evils of telnet - I realise the security risks, but there's little I can do, since I have no admin rights to the SunOS system - ie. it's SEP (somebody else's problem)