In a previous life I did some work on the optimization (by remote
proxying) of the SMB protocol used by Samba [...]  Eventually we said
the heck with it, and sat Samba on top of a different protocol entirely,

The audience are waiting with held breath for more details.

-- Juliusz

They aren't discussable in polite company. Way too much cursing (;-))

Joking aside, that was definitely a case where we said "don't go there".   To the best of my knowledge, there are two network optimization products that do SMB, so it's physically possible.  In our opinion, it was better to use the SMB protocol locally and a different, cached,  protocol over a wide-area network.  I actually prototyped it with Solaris NFS and cachefs, and was pleasantly surprised it worked for a single-writer case.

--dave

-- 
David Collier-Brown,         | Always do right. This will gratify
System Programmer and Author | some people and astonish the rest
davecb@spamcop.net           |                      -- Mark Twain