do the following command
CUE#show voicemail limits
Default Mailbox Size (seconds): 420
Default Caller Message Size (seconds): 60
Maximum Recording Size (seconds): 900
Default Message Age (days): 30
System Capacity (minutes): 480
Default Prompt Language: en_US
Operator Telephone: 0
if u look at the line
System Capacity (minutes): 480
this is the system capacity in minutes
if AIM-CUE (512 MB) Hours of storage 8
if AIM-CUE (1 GB) Hours of storage 14
so upon the above example we do divide the number of minutes on 60 to make it in houres
480/60 = 8
then it is AIM-CUE (512 MB) easy trick :)
good luck
please, if helpful rate