bug#3879: 23.0.96; can't previous-line

In GNU Emacs 23.0.96.1 (i486-pc-linux-gnu, GTK+ Version 2.16.4)
 of 2009-07-18 on elegiac, modified by Debian
 (emacs-snapshot package, version 1:20090717-1)

Save the body of this message starting at this line in a file a.txt.
Now do
$ emacs -Q a.txt
Now maximize the window by the X windows icons at the top right corner, or just hit ALT F10.
Now hold down the down arrow key until you get to the bottom of the file.
Now hold down the up arrow key. You get stuck at the long line. Same with ^P.
Yes you might say that is intentional, but you blew it by letting ^N or down arrow do one thing that ^P or up arrow can't.
Also one has to maximize the window first (here with icewm, xdm), to trigger the bug.

	<description><p>protected "[[<a href="/index.php?title=%E8%81%AF%E7%B5%A1" title="聯絡">聯絡</a>]]"</p>
<p><b>New page</b></p><div></div></description>
	<pubDate>Fri, 17 Jul 2009 21:33:19 GMT</pubDate>			<dc:creator>WikiSysop</dc:creator>		<comments>http://transgender-taiwan.org/index.php?title=%E8%A8%8E%E8%AB%96:%E8%81%AF%E7%B5%A1</comments>		</item>

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