Extension Manager EM_SCHRETRIEVE - Broken in R6?

I’ve run into serious problems using the EM_SCHRETRIEVE notification event (extension manager, client side). Using R5-databases (with either Notes 5 or Notes 6) this event is triggered when I check the availability of other invitees of the meeting (scheduler). Unfortunately this seems to be broken when I use a R6-database (Notes 6 standalone or against Domino 6): When I request the scheduler to display the free time information this event does not show up. Am I missing anything?

In the API documentation the EM_SCHRETRIEVE event is flagged as “modified”, but I couldn’t find a description of this modification.

Your help is very much appreciated,

Chris