Cannot access localhost in another container

General
1

I have two tomcats with belonging .war deployed in containers. One app (in the first tomcat) is addressing services from the second app (and thus container) via localhost:port/service/... call.

One run cmd:

$ sudo docker run -it --rm --name portal --dns company.dns.server.ip --link middleware -p 8180:8180  portal

Middleware has access to db and internet BUT portal is not accessing services from middleware! So, how to solve this whithout changing .war files?

ADDITION:
It seems like it is a connection prob in the level of tomcat / java:
javax.ws.rs.NotFoundException: HTTP 404 Not Found

Thanks.