Scalability design in the mobile Internet web servers is increasing its importance. The performance improve- ment for scalable mobile Internet service requirement is in- creased as the mobile Internet penetrates into every day life. The mobile Internet enabled opportunities for subscription- based charged content for content providers. In order to cope with the scalability design issues, it is important to identify the bottlenecks and propose improvement in the practical use scenes. The author analyzed a content adap- tation system for subscription-based content. The author identified the inefficiencies in the subscription check part and the content adaptation part. The author proposes a novel approach, a trap-door method, to minimize the sub- scription check overhead and the adaptation overhead. The trap-door method utilizes the authentication only at the first access to the charged content. The processing flow is de- scribed. The performance improvement based on the real server performance observation is discussed.