Expat/windows-1256(arabic) code page

Hello,
I found your project(Expat) very useful so i intend to use it in my
project. For this i need to parse an XML file that has windows-1256(Arabic)
code page. But at the start of parsing the "unknown encoding" error be
displayed on the screen. because Expat by default doesn't support
windows-1256 code page. so how can be added windows-1256 code page to the
original expat source files? Is there any 3rd-party sources that can be
applied for Original Expat ?

Please guide me...

Regards,
Behnam Arazkhani