Server media mount not possible

Hi,

We are running ADSM-V2 and ADSM-V3 server, who are sharing 2
  3590-drives in a 3494-tapelibrary. ADSM-V2 has 4 drives, ADSM-V3 has
  2 drives. If ADSM-V2 is using all the 4 drives, any backup started to
  V3 is aborted with "Server media mount not possible".
  These errors didn't exist in the same situation with V2 and V2, the
  backup(s) were just waiting for a mount point till it becomes available.

# dsmc i /var
ADSTAR Distributed Storage Manager
Command Line Backup Client Interface - Version 2, Release 1, Level 0.8
(C) Copyright IBM Corporation, 1990, 1997, All Rights Reserved.

Session established with server ADM_SERVER: AIX-RS/6000
  Server Version 3, Release 1, Level 2.0
  Server date/time: 10/22/1998 11:47:16   Last access: 10/22/1998 11:05:13

Incremental backup of file system: '/var'
Normal File-->           3,648 /var/adm/wtmp  Sent
Normal File-->       1,048,576 /var/adm/ras/errlog  ** Unsuccessful **
Retry # 1  Normal File-->           3,648 /var/adm/wtmp  ** Unsuccessful **
ANS4228E Sending of object '/var/adm/wtmp' failed
ANS4312E Server media mount not possible
Retry # 1  Normal File-->       1,048,576 /var/adm/ras/errlog  ** Unsuccessful 
**
ANS4228E Sending of object '/var/adm/ras/errlog' failed
ANS4312E Server media mount not possible
Retry # 1  Normal File-->           1,781 /var/adm/sara/prtcheck.log  ** 
Unsuccessful **
ANS4228E Sending of object '/var/adm/sara/prtcheck.log' failed
ANS4312E Server media mount not possible
Retry # 1  Normal File-->          10,253 /var/spool/adsm/dsmerror.log  ** 
Unsuccessful **
ANS4312E Server media mount not possible

And the backup is aborted.

dsmerror.log :
10/22/1998 11:47:20  ANS4228E Sending of object '/var/adm/wtmp' failed
10/22/1998 11:47:20  ANS4312E Server media mount not possible
10/22/1998 11:47:20  ANS4228E Sending of object '/var/adm/ras/errlog' failed
10/22/1998 11:47:20  ANS4312E Server media mount not possible
10/22/1998 11:47:20  ANS4228E Sending of object '/var/adm/sara/prtcheck.log' 
failed
10/22/1998 11:47:20  ANS4312E Server media mount not possible
10/22/1998 11:47:20  ANS4312E Server media mount not possible

(V3)activitylog:
10/22/1998 11:47:16  ANR0406I Session 713 started for node ADM_SOBEK (AIX)
                      (Tcp/Ip 10.0.0.35(2127)).
10/22/1998 11:47:23  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:23  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:23  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:23  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:24  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:24  ANR0535W Transaction failed for session 713 for node
                      ADM_SOBEK (AIX) - insufficient mount points available to
                      satisfy the request.
10/22/1998 11:47:24  ANR0403I Session 713 ended for node ADM_SOBEK (AIX).


Anyone any suggestion?

Cheers,
Henk ten Have.