I try to call a web service that has an array of string as a parameter so I used a domaintoxml_mapping to fill that advanced parameter by mapping an list of entity to that parameter but when I run, It shows me this exception in the consol ! org.apache.axiom.om.OMException: localname can not be null or empty at org.apache.axiom.om.impl.llom.OMElementImpl.<init>(OMElementImpl.java:122) at org.apache.axiom.om.impl.llom.OMElementImpl.<init>(OMElementImpl.java:138) at org.apache.axiom.om.impl.llom.factory.OMLinkedListImplFactory.createOMElement (OMLinkedListImplFactory.java:95)