Problem with libxml2 and Unicode char in XML Soap with Qotes (") and "

I'm using libxml2 for SOAP-Actions in an iPhone App.

The big problem is that i want send an SQL-Statement with

开发者_如何学编程NSString *query = @"SELECT test FROM database WHERE test = \"string\""

But libxml2 converts the qotes " into "

Any ideas how to prevent this?

Quotations within the texual data of XML are supposed to be converted to ", per the XML specification. The receiver is responsible for converting " back to quotations when extracting the text from the XML.