In the recent years, web systems have undergone dramatic changes, since they have evolved from plain publishing-oriented facilities to sophisticated service providers. This work describes a practical experience in the provision of limited exposure services on the web. In particular, the paper illustrates functions and procedures for requesting, issuing, and installing digital certificates, which are used to access the services provided by a web portal. Digital certificates are an effective means for authenticating users in a networked environment. Users who participate in the experiments, can install their personal certificate on their favourite browser, and enter personalized service areas.