it has already been mentioned in this post : https://community.jboss.org/message/744530#744530 , you can just ask the resteasy module to not scan for other JAX RS implementations in your webapp; just add this to your web.xml :
<context-param>
<param-name>resteasy.scan</param-name>
<param-value>false</param-value>
</context-param>
<context-param>
<param-name>resteasy.scan.providers</param-name>
<param-value>false</param-value>
</context-param>
<context-param>
<param-name>resteasy.scan.resources</param-name>
<param-value>false</param-value>
</context-param>
worked fine for me