Handbook:Advanced Server Configuration:Local Identifier Support
The facsimile communication protocols include messages that identify the sending and receiving devices using a 20-character string. The T.30 facsimile protocol specifies that these strings should use only numbers, the "+" symbol, and space. Many fax machines and modem however are capable of accepting a wide range of ASCII characters. By default HylaFAX will use the canonical form of the local phone number for the local identity when sending or receiving facsimile. This phone number is specified with the per-modem FAXNumber configuration parameter. If the LocalIdentifier parameter is specified, however, HylaFAX will use it instead. Unlike FAXNumber which is converted to a canonical form that conforms to the T.30 specification, the value of the LocalIdentifier can be any ASCII string; for example,
LocalIdentifier: "Errno Consulting"
Beware that not all Class 2 and Class 2.0 fax modems support arbitrary ASCII local identifier strings. If you encounter problems verify your modem supports this functionality by sending the following commands (if it is a Class 2 modem):
AT+FCLASS=2 OK AT+FLID=? (20)(32-127) OK
The response to the AT+FLID=? command should indicate the range of ASCII characters the modem will accept in a local identifier string.