[xml] Can I allocate the memory for a xml-tree by myself?

[Ronny Seemann <rseemann konplan com>]

Hello

While using the parser module from libxml2 for parsing a XML document, it 
allocates the memory that is required itself. 
Is there a possibility in libxml2 to allocate this memory by myself. I would 
like to allocate my own memory, in order to give over that chunk to e.g. 
xmlParseFile(char *), where the xml-tree can be created.

Thx Ronny