а ви впевнені що ваш custom DNS server application зможе слухати і відповідати 53 порт на GAE ?
мені здається вам в IAAS-cloud треба amazon/rackspace/etc...
http://code.google.com/appengine/docs/whatisgoogleappengine.htmlThe Sandbox
Applications run in a secure environment that provides limited access to the underlying operating system...
Examples of the limitations of the secure sandbox environment include:
- An application can only access other computers on the Internet through the provided URL fetch and email services. Other computers can only connect to the application by making HTTP (or HTTPS) requests on the standard ports.
