Sure you can have client1
and client2
in the same UCM project, since their root path would be different.
However, their UCM component name must also be different, especially if vob1 and vob2 have the same UCM Admin Vob (Ie the same pvob).
The cleartool mkcomp
page does mention:
The component name must be unique within the PVOB.
All UCM objects share the same namespace. You will get an error if the name you provide collides with the name of an existing UCM object, for example, a project.