Description:
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My RSS parser failed after I upgrade the PHP version on my server from 4.x to 5.2. When I debugged the code, I found the error was caused by the xml_parse() function's failure to parse the UTF-8 encoded RSS message, which is originally converted from a GB18030 string. 

The error message looks like: 
"Warning: xml_parse() [function.xml-parse]: input conversion failed due to input error, bytes 0x9B 0xE6 ..."

The orginal GB encoded string consists of Chinese characters, but I converted it to UTF-8 coding using function iconv(). I can view the converted string correctly on web browsers, which means that there is no converting error. So the failure only comes from xml_parse() function, I believe.

For your testing purpose, an example of the original GB18030 string can be downloaded at http://www.la-chinese.com/forum/rss.php?f=19

Thanks!



Reproduce code:
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// variable $gb contains the GB encoded string, e.g., from
// web address http://www.la-chinese.com/forum/rss.php?f=19

// variable $utf contains the UTF-8 string converted from 
// the original GB encoded string

        $urf = iconv('GB18030','UTF-8', $gb);

// function feed_start_end and feed_end_element etc. are from
// the package Magpierss http://magpierss.sourceforge.net/

        xml_set_object( $parser, $this );
        xml_set_element_handler($parser, 
                'feed_start_element', 'feed_end_element' );
                        
        xml_set_character_data_handler( $parser, 'feed_cdata' ); 
    
        $status = xml_parse( $parser, $utf );


Expected result:
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No error message.

Actual result:
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Warning: xml_parse() [function.xml-parse]: input conversion failed due to input error, bytes 0x9B 0xE6 ...