Easy to use, interactive web applications accumulating data from heterogeneous sources represent a recent trend on the World Wide Web, referred to as the Social Web. There however, security standards are often disregarded in favor of interface design or brand new features. This prevents the new services from gaining ground in the enterprise, in medical or e-government environments. We propose the deployment of XML Digital Signatures on web content and demonstrate how an architecture enabling for various security properties would look like. The solution proposed will benefit from the research on security engineering in Service-Oriented Architectures and thus allows for an in-depth analysis on the results.