RFC7303 clarifies that there is no difference between text/xml and
application/xml.
The registration information for text/xml is in all respects the same as that given for application/xml above (Section 9.1), except that the "Type name" is "text".
SOAP is, however, a pretty old protocol and each media type is treated differently.
text/xml is the SOAP 1.1 content type and application/soap+xml is the
content type for SOAP 1.2.
Axis2 will use SOAPMessageFormatter for those content types while
application/xml is only used to format the XML using ApplicationXMLFormatter
which won't generate a proper SOAP request.
You can set SOAP version on the client using setSOAPVersionURI() method i.e.
serviceClient.getOptions().setSoapVersionURI(
org.apache.axiom.soap.SOAP11Constants.SOAP_ENVELOPE_NAMESPACE_URI);