Can you see it if you run bpimmedia or bpmedialist from the comand line?

IE: bpmedialist -U -mlist -ev L74004

     bpimmedia -U -mediaid L74004

Maybe it is encrypting.  I see the following in the bpmedialist command. 

<root@hioshspsbck01:/:16>$ bpmedialist -U -mlist -ev H03056

Server Host = hioshspsbck02

 id     rl  images   allocated        last updated      density  kbytes restores
           vimages   expiration       last read         <------- STATUS ------->
--------------------------------------------------------------------------------
H03056   0      9   09/26/2008 16:24  09/26/2008 16:44   hcart    14502720     0
                9   10/03/2008 16:44        N/A         ENCRYPTION

<root@hioshspsbck01:/:!>$ bpimmedia -U -mediaid H03056

Backup-ID            Policy     Type  RL  Files   C  E  T  PC  Expires
Copy Frag    KB Type Density FNum      Off       Host       DWO MPX Expires          RL MediaID
------------------------------------------------------------------------------------------------

hioshspsbck01_122247 test_nbu_e FULL  0   12099   N  N  R  1   16:44 10/03/2008
 1   1  2000000 RMed hcart   8         191158    hioshspsbc 601 N   16:44 10/03/2008 0  H03056
 1   2   269632 RMed hcart   9         222410    hioshspsbc 601                         H03056

hioshspsbck02_122247 test_nbu_e FULL  0   193059  N  N  R  1   16:24 10/03/2008
 1   1  2000000 RMed hcart   1         2         hioshspsbc 300 N   16:24 10/03/2008 0  H03056
 1   2  2000000 RMed hcart   2         31254     hioshspsbc 300                         H03056
 1   3  2000000 RMed hcart   3         62506     hioshspsbc 300                         H03056
 1   4  2000000 RMed hcart   4         93758     hioshspsbc 300                         H03056
 1   5  2000000 RMed hcart   5         125010    hioshspsbc 300                         H03056
 1   6  2000000 RMed hcart   6         156262    hioshspsbc 300                         H03056
 1   7   233088 RMed hcart   7         187514    hioshspsbc 300                         H03056
<root@hioshspsbck01:/:!>$

While, a tape I know is not encrypted will show the following information, without an "ENCRYPTED"  label.

 <root@hioshspsbck01:/:!>$ bpmedialist -U -mlist -ev H03104
Server Host = hioshspsbck01

 id     rl  images   allocated        last updated      density  kbytes restores
           vimages   expiration       last read         <------- STATUS ------->
--------------------------------------------------------------------------------
H03104   0     39   09/30/2008 07:17  09/30/2008 07:18   hcart    74225312     0
               39   10/07/2008 07:18        N/A         SUSPENDED

It's strange that it's not showing in the GUI report images on media or tape.  They need better documentation if you ask me.  I am also getting ready to use this.

If I read you correctly, where you're looking for "Encryption," you're seeing data referring to the NetBackup Client Encryption Option, which isn't what you're wanting info on.

According to our documentation*, you check for encrypted backups by running the "Images on Media" report and looking for something in the "Encryption Key Tag" column.  Do you have that column in your GUI?

*Veritas NetBackup 6.5.2 Documentation Updates (pages 170-171):

 http://support.veritas.com/docs/302438

DISCLAIMER: I know zero about KMS but I have (sometimes too much) faith in our documentation ;-)

I've just perform this problem to. I've update my administration console to 6.5.2 and the Encryption Key Tag is now avaiable from the report Images on Media