M-RET and M-UP/DOWN not working in Emacs org-mode in console/terminal

Question

I\'m using emacs23 on Ubuntu 32-bit 10.04/10.10 with GNOME and Compiz.

Pressing M-RET in an org-mode plain list in Emacs (GUI) ins

Answer 1

Alternative key combinations exist

for equivalent to M-RET M C-m "" is the Return ↩ key while emacs runs in a graphical user interface.

"RET" is the Return ↩ key while emacs runs in a terminal.

"RET" is also equivalent to "C-m" (【Ctrl+m】). (http://ergoemacs.org/emacs/emacs_key_notation_return_vs_RET.html)

as equivalents for M- you can use

ESC-
ESC-