strip_tags() fails with greater than in attribute

 [2007-02-10 15:46 UTC] geoffers at gmail dot com

Description:
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The following valid (X)HTML is not stripped (this has been 
reported before and closed claiming it is invalid ? read the 
SGML and XML specifications ? this is completely valid).

Reproduce code:
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<?php

echo strip_tags('<span title="test > all">this</span>');

?>

Expected result:
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this

Actual result:
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 all">this