In the focusing on the important of wireless internet, mobile terminal device plays a central role in tracking and coordinating terms in mobile business processing. Especially, mobile device has been considered as a key technology for embedded software and ubiquitous era. Because existing web environments is moving to wireless internet, the new concepts for wireless internet computing environments has gained increasing interest. Mobile agents provide a new abstraction for deploying over the existing infrastructures. Mobile application systems require the flexibility, adaptability, extensibility, and autonomous. New software developments methodology is required to meet the requirements. In this paper, we present an agent architectures model that allows compassable components with pluggable and independable. Our approach involves wrapping components inside a servlet. We have used the model and components to develop the PDA mobile agent.