As I said, the structure of the other file is same..
Here is another file anyway

<A id="a1">
 <B id="b2">
   <C id="c1">
        <D>d1</D>
        <D>d2</D>
   </C>
   <C id="c2">
        <D>d3</D>
   </C>     
 </B>
 <B id="b3">
   <C id="c1">
        <D>d1</D>
        <D>d2</D>
   </C>
   <C id="c2">
        <D>d3</D>
   </C>     
 </B>

</A>
<A id="a2">
 <B id="b4">
   <C id="c1">
        <D>d1</D>
        <D>d2</D>
   </C>
   <C id="c2">
        <D>d3</D>
   </C>     
 </B>
 <B id="b5">
   <C id="c1">
        <D>d1</D>
        <D>d2</D>
   </C>
   <C id="c2">
        <D>d3</D>
   </C>     
 </B>

</A>
[download]

Where I would look for libxml? on my system..
I have hard time installing XML::Parser on my system mainly due to expat.
I would appriciate, if someone can put steps to install XML::Parser locally with 'exact' example.
Thanks, Artist