font-lock question

[Klaus Zeitler <kzeitler@alcatel-lucent.com>]

For many years I had the following statement in my .emacs file:

(defun show-tabs () "Show tabs with a slightly changed background"
  (font-lock-add-keywords nil '(("\t"  (0 'tab-face t))) t))
(add-hook 'font-lock-mode-hook 'show-tabs)

This has worked without any problems up to 22.1.
In version 22.2 and 23 I do have problems with syntax highlighting due
to these few lines above, e.g. when I try M-x list-faces-display
all colors are gone.

So here's my question. Did that only work by accident in older versions?
Maybe I have to change this code slightly for 22.2 and CVS version, but I
can't see what's wrong, when I look at the docu for font-lock-add-keywords.

Klaus

-- 
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|  Klaus Zeitler      Alcatel-Lucent               |
|  Email:             kzeitler@alcatel-lucent.com  |
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