A method and system for using a wireless enabled portable computer system as a wireless modem. The portable computer system may be a personal digital assistant (PDA) having an internal wireless modem. The internal wireless modem, e.g., GSM radio, contains a communication port (port2) that communicates with a processor of the portable computer system. The portable computer system also contains another communication port (port1) that is externally available for connection to a second computer system. A software bridge is provided that copies commands and/or data from the port1 over to the port2 and vice-versa. The software bridge allows the second computer system to directly use the internal wireless modem of the portable computer system when the portable computer system is connected to the second computer. The connection to the second computer system can be made by a wired connection (e.g., serial interface, RS232) or by a wireless connection, e.g., Bluetooth or infra-red communication. The port1 and the port2 can be serial communication ports which may be UART compliant. The PDA thus extends wireless functionality to a second computer system (e.g., a notebook) using conventional connection mechanisms for communicating with the second computer system.