Newbie tunneling help needed

I've been using ssh for years but never had to set something like this up before. I tried searching for tunneling info and found a ton but none describing what I need. Most of the info was for tunneling a service. Here is the layout and what I am trying to do. . .I hope someone can help:

I have three machines, I'll call them Box1(B1) B2 and B3. Due to network layout B1 has no route to B3. B1 can talk to B2 and B2 can talk to B3. Until now when I needed access to B3 I would just ssh manually from B1 to B2 and then again to B3. More or less relaying my connection. I want to make that more permanent. How do I set up B2 so that when it gets a ssh connection from B1 on some arbitrary port it relays it to B3 more transparently? I am only looking to relay the ssh connection not another service. SSH is the service I need.

Thanks for any help in advance.

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Darren R. Weber
email: darren.weber@bellsouth.com
by I-Pager at: dweber4@imcingular.com
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