My WSDL defines

<xsd:element name="GetECSpecNames" type="impl:EmptyParms"/>
<xsd:element name="GetECSpecNamesResult" type="impl:ArrayOfString"/>

When this method (GetECSpecNames) is invoked it creates a soap reply
packet as like below is created

<GetECSpecNamesResult xmlns="urn:epcglobal:ale:wsdl:1">
<item xmlns="" xsi:type="xsd:string">firstSpec</item>
<item xmlns="" xsi:type="xsd:string">firstSpec</item>
<item xmlns="" xsi:type="xsd:string">TestSpec</item>
</GetECSpecNamesResult>

but the Client Accessing this method is expected a soap packet as follows
<GetECSpecNamesResult xmlns="urn:epcglobal:ale:wsdl:1">
<string xmlns="">TestSpec</string>
</GetECSpecNamesResult>

What can be the possible error?