I am writing my first major mode and in many ways it is going well.  As one
of the last steps, I want to write my own newline-and-indent function.  I am
having trouble getting my function called when I press return.  I have the
following in my local keymap for the mode:

(define-key pypoutline-mode-map "\C-j" 'pypoutline-newline-and-indent)
    (define-key pypoutline-mode-map [<return>]
'pypoutline-newline-and-indent)
    (define-key py-mode-map "\C-m" 'pypoutline-newline-and-indent)

but none of them seem to be working.  If I type C-h k and then hit return
(in a buffer running my mode), I get:

RET (translated from <return>) runs the command newline
  which is an interactive compiled Lisp function in `simple.el'.
It is bound to RET.
(newline &optional arg)

Insert a newline, and move to left margin of the new line if it's blank.
If `use-hard-newlines' is non-nil, the newline is marked with the
text-property `hard'.
With arg, insert that many newlines.
Call `auto-fill-function' if the current column number is greater
than the value of `fill-column' and arg is nil.


What am I doing wrong?  Is there something I need to add to the syntax table
of my mode or somewhere else?

Thanks,

Ryan