Here the results:
- the proposed Solution allowed for resolving the "Unable to locate Spring NamespaceHandler" issue
- it did not, at first resolved "ALL" the problems related to the correct resolution of local *xsd schemas: there were still an issue with the schema http://www.springframework.org/schema/beans/spring-beans-2.0.xsd. This issue was raised when trying to execute the program without having an access to internet...
15:58:17,984 FINE (http-localhost-127.0.0.1-8080-1) org.apache.cxf.bus.spring.BusEntityResolver.resolveEntity Attempting to resolve systemId http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
15:58:17,984 WARN (http-localhost-127.0.0.1-8080-1) org.apache.cxf.bus.spring.ControlledValidationXmlBeanDefinitionReader.warning Ignored XML validation warning: org.xml.sax.SAXParseException; lineNumber: 12; columnNumber: 74; schema_reference.4: Failed to read schema document 'http://www.springframework.org/schema/beans/spring-beans-2.0.xsd', because 1) could not find the document; 2) the document could not be read; 3) the root element of the document is not <xsd:schema>.
at org.apache.xerces.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:196)
at org.apache.xerces.util.ErrorHandlerWrapper.warning(ErrorHandlerWrapper.java:97)
at org.apache.xerces.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:386)
- being now instructed on how to face with such issu, I simply adapt the jboss deployment for including the META-INF elements of the module where thoses resources resides (namely 'org.springframework.spring"'). Here the revisited jboss-deployment-structure
<jboss-deployment-structure xmlns="urn:jboss:deployment-structure:1.1">
<deployment>
<dependencies>
<module name="com.oracle" export="true" />
<module name="com.logibec.parameters" export="true" /> <!-- parameters -->
<module name="org.apache.cxf.impl" export="true">
<imports>
<include path="META-INF"/>
<include path="META-INF/cxf"/>
</imports>
<exports>
<include path="META-INF"/>
<include path="META-INF/cxf"/>
</exports>
</module>
<module name="org.apache.cxf" export="true">
<imports>
<include path="META-INF"/>
<include path="META-INF/cxf"/>
</imports>
<exports>
<include path="META-INF"/>
<include path="META-INF/cxf"/>
</exports>
</module>
<module name="org.springframework.spring" export="true">
<imports>
<include path="META-INF"/>
</imports>
<exports>
<include path="META-INF"/>
</exports>
</module>
</dependencies>
</deployment>
</jboss-deployment-structure>
Now the program behaves as expected...
THANKS a LOT Alessio in supporting a newbee.
Best regards