I tried to expire a tape without success, Our environment is Netbackup 7.1 Master and media servers

I rant the command below,  however it states that I had an invalid command paramter, I then ran a second command against that media, however nothing jumped out at me,   What am I missing.???

C:\>bpexpdate -m VTL337 -d 0
Media VTL337 is due to expire at 10/21/2011 11:55:22
Are you sure that the data on this media is not critical to
your business, and you are sure you want to delete VTL337 y/n (n)? y
invalid command parameter

C:\>nbemmcmd -listmedia -mediaid VTL337
NBEMMCMD, Version:7.1
====================================================================
Media GUID:                     24413177-2d5e-40c8-980c-d876be183a16
Media ID:                       VTL337
Partner:                        -
Media Type:                     HCART3
Volume Group:                   ---
Application:                    Netbackup
Media Flags:                    1
Description:                    LTO3 Tapes
Barcode:                        VTL337
Partner Barcode:                --------
Last Write Host:                cbsnbk011
Created:                        08/15/2011 12:31
Time Assigned:                  09/20/2011 11:33
First Mount:                    08/20/2011 23:43
Last Mount:                     09/20/2011 12:07
Volume Expiration:              -
Data Expiration:                10/21/2011 11:55
Last Written:                   09/20/2011 11:55
Last Read:                      -
Robot Type:                     NONE
Robot Control Host:             -
Robot Number:                   -
Slot:                           -
Side/Face:                      -
Cleanings Remaining:            -
Number of Mounts:               33
Maximum Mounts Allowed:         0
Media Status:                   MPX
Kilobytes:                      548677
Images:                         1
Valid Images:                   1
Retention Period:               3
Number of Restores:             0
Optical Header Size Bytes:      1024
Optical Sector Size Bytes:      0
Optical Partition Size Bytes:   0
Last Header Offset:             0
Adamm Guid:                     00000000-0000-0000-0000-000000000000
Rsm Guid:                       00000000-0000-0000-0000-000000000000
Origin Host:                    NONE
Master Host:                    cbsnbk011
Server Group:                   NO_SHARING_GROUP
Upgrade Conflicts Flag:
Pool Number:                    5
Volume Pool:                    Backups
Previous Pool Name:             Scratch
Vault Flags:                    -
Vault Container:                -
Vault Name:                     -
Vault Slot:                     -
Session ID:                     -
Date Vaulted:                   -
Return Date:                    -
====================================================================