> While reviving midas on midtig01 after it was not used for a while ... 
> [local:tigress:S]/>scl -w
> Name                Host                Timeout    Last called
> mhttpd              midtig01.triumf.ca  10000      -2037131082

These clients cannot be deleted. I tried:
1) shutdown from mhttpd "programs" page -> "cannot shutdown client"
2) "sh mhttpd" from odbedit -> 
   [midas.c:5298:cm_shutdown] cannot connect to client mhttpd on host
   midtig01.triumf.ca, port 32853
   Client mhttpd not active
3) in odbedit: "cd /system/clients; rm xxxx"
   refuses to delete the key

Lacking any better ideas, I deleted them via brain surgery on the odb file:
1) stop everything
2) ipcrm the SYSV shared memory segment
3) odbedit -> save xxx.odb
4) xemacs xxx.odb, delete offending odb entries
5) rm .ODB.SHM
6) odbedit -> load xxx.odb
7) voila, bad clients gone, gone, gone.

K.O.