Well, it seems the answer is yes and no. 
Yes, the kernel is able to handle the devices.
No, dxadvfs cannot handle them (coming up in 4.0, I've heard), but the 
commandline utilities can.
But what I ran into seems to be a bug, probably in the kernel, when 
starting up advfs. After a reboot my system, showfdmn says:
              Id              Date Created  LogPgs  Domain Name
3208709a.00002126  Wed Aug  7 13:31:54 1996     512  kitty
  Vol   512-Blks        Free  % Used  Cmode  Rblks  Wblks  Vol Name 
   2     3657728      675504     82%     on    128    128  /dev/rz0g
   3L    7880704     1503184     81%     on    128    128  /dev/rz0g
      ----------  ----------  ------
        11538432     2178688     81%
'Vol Name' of 'Vol 2' SHOULD be /dev/rzb0g, i.e. LUN 1 !!!
 
I think the problem is one of the following: (or a combination)
1) The Log is not on Volume 1 (It works ok on another machine where the 
   log is on volume 1.
2) The Log is not on the lowest numbered volume
3) There is no volume 1
The biggest problem here is that I've lost 'control' of the volumes in 
the domain. addvol will nicely add new volumes, but rmvol removes volumes 
at random, leaving /etc/fdmns in a completely inconsistent state! 
I run 3.2D-1 (rev 41), if anybody knows about patches I'd love to hear 
about it!
Regards, Harald
Harald Lundberg <hl_at_tekla.fi>;Tekla Oy,Koronakatu 1,FIN-02210,ESPOO,FINLAND
tel +358-{0-8879449work,0-8039489fax,0-8026752,11-2418013res,50-5578303mob)
Received on Wed Sep 04 1996 - 08:41:17 NZST