Updating Internal LUA with no Internet access from an external LUA Server

I have read the following two references: 
http://www.symantec.com/business/support/index?page=content&id=TECH106254 

http://www.symantec.com/business/support/index?page=content&id=TECH105741 

The environment variables are as below: 
1. Internal Server - IP1 
2. External Server - IP2 

In internal server, I set the source server pointing to "http:IP2:7070/clu-prod" for update content. 
However, in the event log, it shows "No update found xxxx..." in every scheduled download process. As in the external server, content was successfully downloaded and distributed to the "clu-prod" directory. 

Could I ask how to deal with this situation? 

Please kindly help on this. 

Thanks.