The spontaneous interoperation is an important characteristic of ubiquitous applications and is closely related with mobility. The mobile components in ubiquitous environments are liable to appear in and disappear from one physical space to another. Because this characteristic certainly influences the structure and behavior of applications, they should adapt themselves to the changed environments by configuring their structure and behaviors. Consequently, developers are faced with the above challenging issue when they design and implement ubiquitous applications. The role concept is an efficient tool to model participant entities, their relationship, and collaboration, so role-based model are appropriate to describe a structure and behavior of software system. But, little attention has been given to reflect characteristics of ubiquitous applications. To tackle the problem, this study considers a ubiquitous application as a software organization which consists of software components and proposes an enhanced role-based application model for supporting spontaneous interoperation.