So they are on version R5.0 C01 and the voicemail is pccard small which looks to be 4 mailboxes. User can't get into his vm box because it doesn't exist (would be #5)
I'm also looking online about forwarding to a cell and it looks like it's a 6.0 or later feature?

Toshiba CTX670 with ies32 8 port VM - retired
2 Cisco UC560's and 1 UC540 in a multi site config