Backup Exec Netware Remote agent

Hello,

we need some help with this issue:

we have a win2003 server that provide the backup in to an old netware server 6.5sp7 using the netware remote agent.

Since two day ago the schedule backup fails and we receive this message: 

" e00084ee - An invalid command was sent to the storage device."

Can some one help us  ?

Thanks.