Reverse proxy configuration through j2ee applicaton to RTC using httpClient

Engineering portal(Engp)  provides proxy capabilities for internal daimler applications (similar to reverse proxy),

basically its a j2ee application uses httpClint api from apache to connct backend proxy application. and engineering portal proxy application has the public url

https://eng-daimler.com/Engproxy/app/RTC/ccm

which we map to private url inside daimler n/w https://daimler.zazz.example.com:9443/ccm

when we call the app from browser we get the login page successfully ,but inbetwee RTC will reidrect  to JTS with

https://daimler.zazz.example.com:9443/jts

  the session is not getting created  and when we verified the LTPAToken is missing in cookie , we need to know is any header parameters are missing dure to that RTC is not able to create the user session .

  we gone through the wiki which provides reverse proxy configuration for IHS webserver with RTC , in engineering portal we also use IBM htttp server , through which  requests reach app server(WAS8) , on the app server we deployed the engineering portal application which actually talks to RTC , RTC is again deployed on different app server,