Workflow templates and Tasks not available on the system

[Ronen Fox]

Hello All,
A strange behavior on one of our R3 systems: none of the standard TS & WS
tasks exist. For example, running transaction PFTC and trying to display the
notification of absence workflow WS 30000015, gives an error 'object does
not exist'.
When searching for tasks using the input help, results are displayed, but
when trying to select one of the results, again the message 'object does not
exist' occurs.
This is a 4.6c system upgraded from 4.0b and it's the first time we try to
use workflow in it. The workflow customizing in SWU3 has been preformed
correctly.
Please advise if you have encountered a similar situation.
Thanks a lot,
Ronen Fox