SMB protocol help

[Derrell.Lipman at UnwiredUniverse.com]

Hi.  I'm a seasoned protocols engineer, but new to SMB and Samba.  Two
questions:

1. Where can I find SMB protocol specs?  (This must be a FAQ; I've
   searched for a FAQ list but can not locate one.)

2. If a Win95 machine can see a Win2000 machine in Network
   Neighborhood, and the Win2000 machine can see the Win95 machine in
   My Network Places, and the Linux Samba machine can use smbclient to
   directly access either of those, why wouldn't the Samba machine be
   able to see either the Win95 machine or the Win2000 machine using
   smbtree?

Thanks!

Derrell