Recusrive Functions in 7.0.3

Are recursive functions allowed in in 7.0.3 as I seem to be unable to get them to work in plpgsql, it just freezes and
Ihave to do ctrl-alt-c.
 
ie calling the same function name from within some form of loop, possible to 4 or 5 levels?

Also is it possible to output any debugging info, all I really want to be able to do is print out a variable to the
screen.

Final quesion for pure speed on functions does PL/PGSQL have special compilation options or would I get better
performacefor PL/C?
 

Regards

Mark