@ paai:

Yes, it can be any cellphone to send SMS commands to SMSCON.

Only if SMSCON has never been send messages to and phone is stolen
and swapped with other SIM card it will send SMS message to predefined cellphone number (user option SENDERNUMBER in "smscon_config" file).

After this, sending a SMS command to the new SIM card number ('thiefs' SIM card number) it will send return SMS's to your currently used cellphone (and this number is stored in SENDERNUMBER in "smscon_config" file).