configuration.export seems to have some issues :

a) in the export, slashes are escaped by backslashing them. this doesn't seem to be necessary, and does not match the example at http://www.zabbix.com/documentation/2.0/manual/appendix/api/configuration/export

b) there are two excess newlines :
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n
and
<\/zabbix_export>\n