Webdynpro ABAP not working from internet

Hello,

I´m new at webdynpro and portal...

We have a ess portal with webdynpro abap and java. Our employees may access it from intranet and all works fine, and from internet when they are in the outside.

From internet the webdynpro abap gives the message that the server cannot be reached. The server is our production backend and is not open to the exterior.

Is there a way to make this work, from inside and outside?

Teresa