Description:
------------
wddx_deserialize returns NULL when iso-8859-1 encoding is used and packet contains a non-ascii character (ex : ?).

PHP5 is built with libxml.
With PHP4 and EXPAT all is right.

I think the problem come from libxml.

I wrote a script wich call the parser directly and saw that
the callback data function is called once in PHP4 with the entire string, and twice in PHP5.
The first call is done with the first part of the string, until the first accented character (excluded).
Second call with the remainder of the string.

Ex : aaaabbbb????ccccddd

PHP4 : data callback function called with aaaabbbb????ccccddd

PHP5 : data callback function called with
aaaabbbb
then a second time with
????ccccddd



Reproduce code:
---------------
<?php
$data = "<" . "?" . "xml version=\"1.0\" encoding=\"ISO-8859-1\"" . "?" . ">\n";
$data .= "<data><struct><var name=\"screen\"><string>aaabbb????cccdddeee</string></var></struct></data>";

$depth = array();
function beginElement($parser, $name, $attrs)
{
    global $depth;
    $depth[(int) $parser]++;
}
function endElement($parser, $name)
{
    global $depth;
    $depth[(int) $parser]--;
}
function getDatas($parser, $data)
{
	echo $data . "<br>";
}
$xml_parser = xml_parser_create("ISO-8859-1");
xml_set_element_handler($xml_parser, "beginElement", "endElement");
xml_set_character_data_handler($xml_parser, "getDatas");

    if (!xml_parse($xml_parser, $data, TRUE)) {
        die(sprintf("XML error : %s at line %d",
                    xml_error_string(xml_get_error_code($xml_parser)),
                    xml_get_current_line_number($xml_parser)));
    }  
xml_parser_free($xml_parser);
?>

Expected result:
----------------
aaaabbbb????ccccddd

Actual result:
--------------
aaaabbbb
????ccccddd