[Orgmode] Problem with tables

[Gaspaio]

Hello everybody,

I'm a newbie at org-mode (and emacs BTW), and i can't seem to use a few 
commands like table-delete-row, table-insert-row and so on. I systematically 
get a "Table not found" error.
Also, some of the Shift commands don't seem to work, like using S-UP/Down to 
navigate between headers. I tried toggle the org-support-shift-select, but 
nothing.

I'm using emacs.app v23.2 (OSX), with org-mode v7.2

Any ideas ?

Thanks.
Gaspaio