For the following sample:

<&lt;foo&gt;>
    <&lt;oops&gt;>
      some data
    <&lt;/oops&gt;>
<&lt;/foo&gt;>

the following problem occured:
$expr1 = "//foo";
$expr2 = "//*[name()='foo']";

$path1 = xpath_eval($context, $expr1); # no result ??? WRONG
$path2 = xpath_eval($context, $expr2); # one result !!! OK

The two expressions "//foo" and "//*[name()='foo']" should lead to the same result, but they do not.
I have turned Off all magic_quotes in php.ini .

It's to mention, that I use the PHP 4.2.0 Extensions for DOM XML support in my PHP 4.1.0 Version.