The advent of ubiquitous computing has prompted the development of wireless applications within a pervasive computing environment. PDA?s and cell phones are the current logical choice for these implementations. However, the display characteristics of these devices vary greatly, and are certain to continue evolving. In order to handle existing and future breeds of these devices, a configurable, scalable, and maintainable interface, based upon standards definitions, is imperative. In this paper, we present the design and implementation of the EPARK wireless parking payment system built using pervasive computing. Our system utilizes XSLT (eXtensible Stylesheet Language Transformations) of standard XML (eXtensible Markup Language) for performing device adaptability and data validation.