OK, the xml request is as follows
<?xml version="1.0" encoding="utf-8"?>
<request xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="BSTU">
<transactionheader>
<username>****</username>
<password>******</password>
<time>30/06/2008 16:17:08</time>
<clientreferencenumber>******</clientreferencenumber>
<information>Some info here</information>
<postbackurl>Postback url here</postbackurl>
</transactionheader>
<transactiondetails>
<items>
*****************
</items>
</transactiondetails>
</request>
That is how it is. But constructing a postback url is still a task for me.Any code snippet or advice would help.