User management

[Peter Kirk]

Hi there,

is there anyone who knows of a java-based user-management system suitable
for integrating with a web-application?

We have a web-application written in java (servlets/jsp) for which we need
to add some user management functions: login; restrict access to data;
create/manage users; etc.

Instead of completely "rolling our own", we would like to know if there is
an existing project out there which we can utilise.

Thanks for any advice
Peter