Using several tapes with ntbackup job

I'm having difficulty setting up automated backups using ntbackup. The first is a normal backup that fires once a week and the second is a differential that fires the other 4 days of the work week (using the same tape).

The difficult part is trying to do that using a different tape for each week of the month.

The tapes are all named 'Weekly'. The description changes for each tape: Week 01, Week 02... I replaced the /g switch (tape guid) with the /p switch (media pool). I tried deleting the /d switch , but noticed it returned with a default of [/d """"], so I changed it to the tape's description (Weekly - 04 in this case).

The backup wouldn't find the tape unless it was in the free media pool!

Is what I'm trying to do possible? Do I need to lose the description? Would I have to use advanced scripting (which I'm not familiar with, but not opposed to trying/learning)? I don't mind trying various fixes, but I have a bunch of other stuff I need to be doing!

Thanks for any help, and here are the current jobs for reference:

C:\WINNT\system32NTBACKUP.exe "@C:\Documents and Settings\...\Weekly.bks" /n "Weekly" /d "Weekly - 03" /v:yes /r:no /rs:no /hc:on /m normal /j "Weekly.job" /l:f /p "4mm DDS"

C:\WINNT\system32NTBACKUP.exe "@C:\Documents and Settings\...\Differential.bks" /n "Differential" /d "Weekly - 03" /v:yes /r:no /rs:no /hc:on /m differential /j "Differential.job" /l:f /p "4mm DDS"