[fw-general] Zend/Pdf: 'Object number must be positive integer'

[Adeel Ahmad Khan]

I'm getting the following exception when trying to load a PDF and read
the metadata:

<b>Fatal error</b>:  Uncaught exception 'Zend_Pdf_Exception' with
message 'Object number must be positive integer' in
/Users/adeel/Sites/j101/lib/Zend/Pdf/Element/Reference.php:95
Stack trace:
#0 /Users/adeel/Sites/j101/lib/Zend/Pdf/StringParser.php(510):
Zend_Pdf_Element_Reference-&gt;__construct(0, 0,
Object(Zend_Pdf_Element_Reference_Context),
Object(Zend_Pdf_ElementFactory))
#1 /Users/adeel/Sites/j101/lib/Zend/Pdf/StringParser.php(333):
Zend_Pdf_StringParser-&gt;_readReference('0')
#2 /Users/adeel/Sites/j101/lib/Zend/Pdf/StringParser.php(460):
Zend_Pdf_StringParser-&gt;readElement()
#3 /Users/adeel/Sites/j101/lib/Zend/Pdf/StringParser.php(307):
Zend_Pdf_StringParser-&gt;_readDictionary()
#4 /Users/adeel/Sites/j101/lib/Zend/Pdf/StringParser.php(570):
Zend_Pdf_StringParser-&gt;readElement()
#5 /Users/adeel/Sites/j101/lib/Zend/Pdf/Element/Reference.php(168):
Zend_Pdf_StringParser-&gt;getObject('47292566',
Object(Zend_Pdf_Element_Reference_Context))
#6 /Users/adeel/Sites/j101/lib/Zend/Pdf/Element/Reference.php(128):
Zend_Pdf_Element_Reference-&gt;_de in
<b>/Users/adeel/Sites/j101/lib/Zend/Pdf/Element/Reference.php</b> on
line <b>95</b>

What does this mean?  I can read it fine with pdfinfo (from xpdf).

Thanks,
Adeel