I tried the ctl-enter, enter, alt everything and ctl everything. None executes "send". Enter starts a new line like you said. I think the Apple wireless keyboard supports "send" and would think somebody has captured the command string, either as the charactors or the ASCII or the HEX values. Don't know what format is used for the keyboard, ASCII or HEX.
I do not have an analyzer for reading the stuff. Maybe somebody out there can capture the string and post the command string(s)...