The advances in the wireless technology, represented by the improved computational capabilities of third generation (3G) and fourth generation (4G) wireless devices and the wider bandwidth wireless networks, make it possible to support a variety of security-sensitive applications such as m-banking and m-commerce. This, however, requires increasingly robust End-to-End security solutions. The contribution of this paper is twofold. First, it presents a design and an implementation of a light weight application-level security solution for handheld devices in wireless LAN. Second, it analyzes the impact of the processing power, time, and memory on the performance of two of the widely known encryption algorithms - RC4 and AES - used by the lightweight handheld devices in the wireless network environment. The work in this paper uses pure Java components to provide endto-end client authentication and data confidentiality and integrity between wireless J2ME-based clients and J2ME-based servers.