MultiDesk will let you have multiple desktops and users under OS/2. While it is still in early beta stages, it already lets you create, delete and manage desktops; define users; customize environment, video resolution, etc for each user; lock some files from other users' eyes; etc.. Desktops and users are created with an easy to use management tool.
Hobbes-Search: md-0-1-9.wpi
Source: OS/2 ORG