Steve's quick list of things that need finishing off:
[they are in no particular order and range from the trivial to the long winded]

 o Proper timeouts on each neighbour (in routing mode) rather than
   just the 60 second On-Ethernet cache value.

 o Support for X.25 linklayer

 o Support for DDCMP link layer

 o The DDCMP device itself

 o PPP support (rfc1762)

 o Lots of testing with real applications

 o Verify errors etc. against POSIX 1003.1g (draft)

 o Using send/recvmsg() to get at connect/disconnect data (POSIX 1003.1g) 
   [maybe this should be done at socket level... the control data in the
    send/recvmsg() calls should simply be a vector of set/getsockopt()
    calls]

 o check MSG_CTRUNC is set where it should be.

 o Find all the commonality between DECnet and IPv4 routing code and extract 
   it into a small library of routines. [probably a project for 2.7.xx]

 o Add perfect socket hashing - an idea suggested by Paul Koning. Currently
   we have a half-way house scheme which seems to work reasonably well, but
   the full scheme is still worth implementing, its not not top of my list
   right now.

 o Add session control message flow control

 o Add NSP message flow control

 o DECnet sendpages() function

 o AIO for DECnet