Communication between android and EC2 with RDS

I have an EC2 instance on AWS configured with Apache tomcat 8 and java. Following some tutorials from here, I can create one .war of my Web Service in eclipse and put it inside webapps folder of tomcat in my EC2 instance. I am able to access this services from the IP address of EC2 with the specific port and .war file name. For example:

IPADDRESS:8080/MyAplication.

And everything seems to work fine, I can open the services and see the wsdl files. My Web Service (in .war file) is configured for make a connection with a RDS instance from amazon. The connection itself is ok, I tested in localhost a direct connection with RDS from Android. But, when I try to connect with services that I put in EC2 (from there
the connection with my RDS is created) from Android, no data returns and I get a Null Pointer. The link that I used to make a connection with EC2 from Android is the Public IP of EC2 and the port (8080), followed by the specific path of wsdl file. For example:

http://ift.tt/1Gnvx1v

I am using the KSOAP library to consume web service on android side and I have no idea of the reason that I don't get data from EC2 instance.

All methods in the web service and the comsumption in android works fine, I tested all in local host.

Anyone have an idea? Thanks!