Is there a way to set a search spec in SSSE

to further control which Siebel activities are synced to the Exchange calendar?  We have various activities that need to be displayed in the user's calendar in Siebel, but we do not whant them synced to Exchange.  Therefore, the "Display In" must be set to "Activities and Calendar".  I cannot find a place to do this.  Can anybody tell me if and where such a place exists?

Thanks