trouble binding to <next> & <prior>

[Mirko <mvukovic@nycap.rr.com>]

Hello,

I have a following keybinding, parts of which do not work.  In
particular I am trying to bind view-previous-entry to the page-up key
on the standard PC keyboard (using Emacs 22.1).  I used both h-k and h-
l to determine that this key is identified with "<prior>" & <next>".

(defvar iop-alert-mode-map nil
  "Keymap for IOP-alert mode")
(unless iop-alert-mode-map
  (setq iop-alert-mode-map (copy-keymap text-mode-map))
  (define-key iop-alert-mode-map (kbd "<prior>") 'view-previous-entry)
  (define-key iop-alert-mode-map (kbd "<next>") 'view-next-entry)
  (define-key iop-alert-mode-map (kbd "d") 'mark-entry-for-deletion)
  (define-key iop-alert-mode-map "m" 'mark-entry-for-save))

When in a buffer with iop-alert mode, doing h-m gives me the following
output on keybindings:
... stuff skipped
< n e		Prefix Command
< p r		Prefix Command
< n e x		Prefix Command
< p r i		Prefix Command
< n e x t	Prefix Command
< p r i o	Prefix Command
< n e x t >	view-next-entry
< p r i o r	Prefix Command
< p r i o r >	view-previous-entry

It seems <prior> and <next> are bound to the character sequence
"<prior>" and "<next>".  Pressing those characters will invoke the
commands.  But pressing the Page-up/down keys will not.

Indeed, doing a h-k shows that page-up/down are still bound to scroll
up/down.

What am I doing wrong?

Thank you,

Mirko