We are running 5.2.0a build 5447. When any of the users go to share Calendar, they only see two users. We have over 10 users. This is also happening when assigning issues. The work-around has been to use the select button and pick the person, but this is does not happened for everyone. Some people can type in a name and it completes but others only get the same two users as the share Calendar issue.

Has anyone else had this issue and how was it resolved?