Panasonic KX-TD1232JT Programming Manual page 241

ISDN extension numbers – [012] ISDN Extension Number Set
Voice Mail extension numbers – [118] Voice Mail Extension Number Set
Phantom extension numbers – [130] Phantom Extension Number Set
Floating numbers – [813] Floating Number Assignment
PS extension number – [671] PS Extension Number Set
Features Guide References
Direct Dialling Inward (DDI)
Integrated Services Digital Network (ISDN)
ISDN Programming
3.2 System Programming
241