When subscribing with no expiration duration, WiseMan is defaulting to a 1 day
duration. If this subscription is then renewed with no expiration, then the
subscription expiration becomes infinite.
WS-Eventing and WS-Management specification allow for infinite subscription
being only ended when unsubscribe is received. To achieve this behavior, one
need to renew the subscription with no expiration. This is not the right behavior.
We need to protect against badly written clients or client that die unexpectedly
so we need such behavior (in such a case, 1 day seems too long) but we also need
the ability to deactivate it.
If EnumerationContext leasing is implemented (lease based on client activity),
we can accept infinite subscription that will be cleared by the leasing processing.