@DuXxXieJ
I don't know what you mean with "echo to" or which prompt "a" command prompt is. You can feed the cmd.exe with /run, like in: "/run cmd /q /c ipconfig /flushdns" (just google for the cmd shell syntax). This may not be of use to you though as I don't know what your "mIRC.cmd" is about.

@chacha
http://en.wikipedia.org/wiki/Cmd.exe