problem with the latest version of ssh

Hi, I.m hoping someone can shed some light on a confusing problem for me. 

I administer 2 servers for sendmail/http/dns and have recently just upgraded 
one of them (a solaris 8 sparc) to OpenSSH_4.0p1, OpenSSL 0.9.7e 25 Oct 2004

The older machine is a redhat 6.2 x86 machine running SSH Version 2.0.13 

 I recently started work at a new company and i am unable to ssh into the 
ssh-upgraded server remotely. Nor will it service http requests from this 
location. The older machine however works just fine and I can ssh in no 
problem. 

The confusing thing is that when I try to access my machines from a friends 
network the upgraded machine works fine and I can log in using ssh.

I am logging in using the latest version of putty on the same win2k m/c in 
every case

Can anyone tell what is about the upgraded ssh/ssl machine that causes it to 
stop responding to ssh requests (and http requests) from one particular 
location but is ok from other locations. The other machine running the older 
version of ssh works fine and I.m able connect to it fine from my new work 
location, 

TIA.