Problem with 3494 / 3590 drives only partly seen by library

Ok, folks got a puzzle for you.   here's the environment:

H80 / AIX 4.3.3 (relatively latest patches)
3494 with 3590 type E drives  (another ADSM and TSM server are also using
this library but different drives)
3590 drives are attached via a SAN datagateway

Ok, the drives are "available" and working because I'm able to do the
following commands:

# mtlib -l /dev/lmcp0 -D -E
 Type   Mod  Serial #   Devnum   Cuid  Device  VTS Library
003590  E1A  13-57297  00572970    1      0
003590  E1A  13-56981  00569810    2      0
003590  E1A  13-56977  00569770    3      0
003590  E1A  13-56746  00567460    4      0
003590  E1A  13-F0336  00F03360    5      0
003590  E1A  13-F0550  00F05500    6      0
003590  E1A  13-34252  00342520    7      0
003590  E1A  13-34228  00342280    8      0   (presently testing this one)
003590  E1A  13-F2074  00F20740    9      0
003590  E1A  13-F1892  00F18920   10      0

#lsdev -Cc tape
rmt0  Available 40-60-00-5,0 SCSI 4mm Tape Drive
rmt1  Available 2A-08-00-0,2 IBM 3590 Tape Drive and Medium Changer
(here's the matching logical device being tested)
rmt2  Available 2A-08-00-0,4 IBM 3590 Tape Drive and Medium Changer
rmt3  Available 2A-08-00-0,6 IBM 3590 Tape Drive and Medium Changer
rmt4  Available 2A-08-00-0,8 IBM 3590 Tape Drive and Medium Changer
lmcp0 Available              LAN/TTY Library Management Control Point

(now I load a tape, write to it and unload the tape here)
#mtlib -l /dev/lmcp0 -x 342280 -m -V A00020
#tar -cvf /dev/rmt1 /etc     (note: rmt1 maps to serial number 342280
checked with the "lscfg -l rmt1 -v" command)
#mtlib -l /dev/lmcp0 -x 342280 -d -V A00020

So, you may be a bit curious why I use the "-x" flag here instead of the "
-f /dev/rmt1" flag!
Well, that's what I've been wondering for the past week and trying to get
Well, that's what I've been wondering for the past week and trying to get
IBM to answer.

(This command doesn't work:)
#mtlib -l /dev/lmcp0 -f /dev/rmt1 -m -V A00020
 Query  operation Error - Device is not in library.

So, I can actually simply the problem even further, Can anybody on this god
forsaken planet
tell me what the hell is wrong (or at least why this first command suceeds
but the 2nd cmd fails)
#mtlib -l /dev/lmcp0 -x 342280 -q D
Device Data:
   mounted volser.............none.
   device category............01F6
   device state...............Device installed in Library.
                              Device available to Library.
                              ACL is installed.
   device class...............3590-E1A
   extended device status.....Suppress unsolicited interrupts
#mtlib -l /dev/lmcp0 -f /dev/rmt1 -m -V A00020
 Query  operation Error - Device is not in library.

Some folks at IBM are saying it's some setting or config that's messed up
but when I ask them what that setting is NO-ONE
I've talked to so far seems to know.  Been like this for a week.

Rick Un
!#@#$%%#$!!!!!!