<process name="HelloWorld" targetNamespace="http://nmsp" xmlns:tns="http://nmsp"     xmlns:buoysnmsp="http://buoys.ws.esimo/" xmlns:xsd="http://www.w3.org/2001/XMLSchema"     xmlns="http://docs.oasis-open.org/wsbpel/2.0/process/executable"...     <import importType="http://schemas.xmlsoap.org/wsdl/" location="hello.wsdl"         namespace="http://nmsp"/>     <partnerLinks>         <partnerLink myRole="Greeter" name="caller" partnerLinkType="tns:Greeter-Caller"> </partnerLink>         <partnerLink partnerRole="BuoysRole" name="BuoysWSJaxWsService"             partnerLinkType="tns:BuoysLink"> </partnerLink>     </partnerLinks>     <variables>         <variable messageType="tns:nameMessage" name="request"> </variable>         <variable type="xsd: int" name="n"> </variable>         <variable messageType="tns:greetingMessage" name="response"> </variable>               <variable messageType="buoysnmsp:BuoysWSJaxWs_getIntArr" name="BuoysWSJaxWs_getIntArr"> </variable>         <variable messageType="buoysnmsp:BuoysWSJaxWs_getIntArrResponse" name="BuoysWSJaxWs_getIntArrResponse"> </variable>     </variables>     <correlationSets>         <correlationSet name="trip" properties="tns:tripLocator"/>     </correlationSets>     <sequence name="MainSeq">                   <receive createInstance="yes" name="ReceiveName" operation="sayHello" partnerLink="caller"             portType="tns:Greeter" variable="request"> </receive>         <assign>             <copy>                 <from>1</from>                 <to variable="n"/>                 </copy>                 <copy>                     <from>$request.name/leafElement[$n]</from>                     <to>$BuoysWSJaxWs_getIntArr.getIntArr/arg0[$n]</to>                 </copy>             <!--</copy>-->         </assign>                <invoke name="InvokeBuoys" operation="getIntArr" partnerLink="BuoysWSJaxWsService"             portType="buoysnmsp:BuoysWSJaxWs" inputVariable="BuoysWSJaxWs_getIntArr"             outputVariable="BuoysWSJaxWs_getIntArrResponse">             <correlations>                 <correlation set="trip" initiate="yes" pattern="in"/>             </correlations>         </invoke>         <assign>             <copy>                 <from>$BuoysWSJaxWs_getIntArrResponse.getIntArrResponse</from>                 <to>$response.greeting</to>             </copy>                    </assign>                 <reply name="SendGreeting" operation="sayHello" partnerLink="caller" portType="tns:Greeter"             variable="response"> </reply>             </sequence> </process>

<definitions targetNamespace="http://nmsp"     xmlns:tns="http://nmsp" xmlns:xsd="http://www.w3.org/2001/XMLSchema"     xmlns:buoysnmsp="http://buoys.ws.esimo/"     xmlns:bpel="http://schemas.xmlsoap.org/ws/2003/03/business-process/&...     xmlns:plt="http://docs.oasis-open.org/wsbpel/2.0/plnktype"     xmlns="http://schemas.xmlsoap.org/wsdl/">     <import namespace="http://buoys.ws.esimo/" location="BuoysWSJaxWsService.wsdl" />     <types>                <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"             targetNamespace="http://nmsp">                    <xsd:element name="newElement" type = "tns:newElement" />                                  <xsd:complexType name="newElement">                     <xsd:sequence>                                                <xsd:element name="leafElement" type = "xsd:double" maxOccurs="unbounded"/>                                                   </xsd:sequence>                 </xsd:complexType>                                  </xsd:schema>            </types>     <message name="greetingMessage">         <part name="greeting" element="tns:newElement" />     </message>     <message name="nameMessage">         <part name="name"  element="tns:newElement" />     </message>     <portType name="Greeter">         <operation name="sayHello">             <input message="tns:nameMessage" />             <output message="tns:greetingMessage" />         </operation>     </portType>     <plt:partnerLinkType name="Greeter-Caller">                <plt:role name="Greeter" portType="tns:Greeter">                    </plt:role>     </plt:partnerLinkType>     <plt:partnerLinkType name="BuoysLink">                <plt:role name="BuoysRole" portType="buoysnmsp:BuoysWSJaxWs">                    </plt:role>     </plt:partnerLinkType>     <bpel:property name="tripLocator" type="xsd:int" />     <bpel:propertyAlias propertyName="tns:tripLocator" messageType="buoysnmsp:BuoysWSJaxWs_getIntArr"     part="getIntArr" />     <bpel:propertyAlias propertyName="tns:tripLocator" messageType="buoysnmsp:BuoysWSJaxWs_getIntArrResponse"     part="getIntArrResponse" />     </definitions>

ERROR [org.jbpm.bpel.sublang.xpath.XPathEvaluator] cannot create element for step with non-numeric predicate: [(DefaultNameStep): arg0]

P.S. it is interasting that if I change "to" in <copy>                     <from>$request.name/leafElement[$n]</from>                     <to>$BuoysWSJaxWs_getIntArr.getIntArr/*arg0[$n]*</to>                 </copy> to <copy>                     <from>$request.name/leafElement[$n]</from>                     <to>$BuoysWSJaxWs_getIntArr.getIntArr/*arg0[1]*</to>                 </copy>