State-of-the-art middleware for component-based distributed applications requires openness to support a broad and varying range of services. It also requires powerful and maintainable composition between application logic and middleware services. In this paper we describe DyMAC (Dynamic Middleware with Aspect-Components), a component and aspect-based middleware framework that supports component-based development of middleware services and offers the power of aspect-oriented composition to connect the application logic to the middleware services. We discuss the issue of a lack of expressive power in the contracts of components and aspects when combining component-based and stateof-the-art aspect-oriented development. We describe how the DyMAC framework offers a component model that solves this problem with aspect integration contracts.