This paper presents a multimodal, service-oriented architecture based on a distributed implementation of W3C's Multimodal Architecture and Interfaces applied to ubiquitous computing. The specific goal is to create a platform able to provide multimodal interactions between people with functional diversity and several semantic services developed by third-party companies and consumed through a display, in order to make content more accessible and interactive. The general purpose of this research is the development and deployment of urban, ubiquitous services for people living in or visiting a city. And the motivating scenario behind the design and development of the multimodal platform and semantic services is one in which people use media poles and confidently interoperate with the surrounding environment in a multimodal way.