I am wrote and deployed a CXF web service into a Tomcat server using the instructions here. The web service deploys fine as I can see the WSDL file in a web browser.
Had this problem when upgrading from CXF 2.3.x to 2.7.x
Added stax2-api and woodstox-core-asl jars from the 2.7.x CXF distribution and the webservice works again.