The RS-232 pins of M-duino are only Rx-Tx, but must of the commercial devices with RS-232 port uses a D-sub9 pin, and (According to Mr. Google and Mrs Wikipedia) the RS-232 standard is supposed to use more pins besides Rx-Tx (DCD, DTR, DSR, RTS...).
If I only use the Rx, Tx and Gnd pins, should the communication work anyway?