System software for future computing environments becomes more complex and heterogeneous. Portability becomes one of the important properties of the future system software. Component-based systems contribute the portability issues. However, component behaviors cause dependencies among components and thus prevent consistent system compositions. We have built a component-based Java virtual machine and tried three configurations with components in order to investigate the inter-component dependencies and the effect of the component behaviors. Also, this paper proposes requirements for a component framework for future ubiquitous computing.