SOAP call in coldfusion

I try to call this as webservice and i am getting error message Web service operation "xmltest" with parameters {} could not be found.
Any idea. Thanks

<cfcomponent>
<cffunction name="xmltest" access="remote" returntype="xml" output="no">
<cfxml variable="BookDetailsXML" >
<?xml version="1.0" encoding="iso-8859-1"?>
<products>
<product>
<name>q</name>
<category>qqqqqq</category>
<bookimage>qqqqqqqqqqq</bookimage>
<desc>qqqqqqqqqqqqqqq</desc>
</product>
</products>
</cfxml>
<cfreturn xmlparse(testxml)>
<cfcontent type="text/xml" reset="yes">
</cffunction>
</cfcomponent>

i need example with xml webserivce. Also how can i pass userid and password in soapheader...