define-key .. whats wrong here?

[Harry Putnam]

This is ocurring in gnus but is an elisp or emacs question so
properly belongs here I guess.

Attempting to define a keys that run macros

>From .gnus.el
  (fset 'delall 
     [?M ?P ?b ?B backspace ?y]) 
   (define-key gnus-summary-mode-map "D" 'delall) 

  (fset 'sendto_spam1 
     [?M ?P ?b ?B ?m ?\C-a ?\C-k ?n ?n ?m ?l ?: ?s ?p ?a ?m ?1 return]) 
  (define-key gnus-summary-mode-map "\C-ss" 'send2_spam1) 

The first one works.
And pressing C-h k <RET> D <RET> in summary buffer shows 
it bound to the macro

The second doesn't throw errors but shows undefined when
running C-h k <RET> C-c s <RET> in summary mode.

I got the example from emacs info:

[...] 
                  (define-key texinfo-mode-map "\C-cp"
                              'backward-paragraph)
                  (define-key texinfo-mode-map "\C-cn"
                              'forward-paragraph)))

Where it is discussing adding hooks.