Reply of e-yes via forum.nitdroid.com;

Send SMS from another phone (using the SIM from your n900)?

or

insend SMS using command line (adb shel, for example):
dbus-send --print-reply --system --dest=org.ofono /isimodem org.of ono.MessageManager.SendMessage string:"+71231234567" string:"test smsko"

can anyone explain this :P