AT$QCPDPP command - Allowed password characters


The AirPrime MC/SL-Series - Extended AT Command Reference document mentions the AT$QCPDPP command (used as AT$QCPDPP=, <auth_type>, , ), which allows setting PAP/CHAP authentication parameters. Does anyone know which characters are allowed in the password parameter? I can not seem to find this information anywhere.

Basically I’d like to know if any 8-bit extended ASCII character allowed, or just a subset? Which characters have special meaning, such as the quotation mark ("), and can these be escaped if they are legal?

Best regards,