Classcastexception seistub cannot be cast to org.apache.cxf.frontend.clientproxy exacttarget fuelsdk

I am trying to use FuelSDK as an osgi bundle by embedding it in another bundle using embed dependency. While using the bundle I am getting this error in the logs - 

java.lang.ClassCastException: com.sun.xml.internal.ws.client.sei.SEIStub cannot be cast to org.apache.cxf.frontend.ClientProxy

I found these links -- http://cxf.547215.n5.nabble.com/wsdl2java-Set-Java-Version-td4301284.html

 where it is written to use a non-cxf client, but we cannot change fuelsdk's code.  Did anyone else face the same issue while integrating cxf with AEM? Any help is appreciated.

Thanks