The Drop Ad hoc Conference When Creator Leaves feature is part of the Conferencing Enhancements and will therefore be unavailable after the Cisco CallManager upgrade from CallManager 3.3(4) to 4.0(1).
If you are currently using any of these features (FAC and CMC, Conferencing Enhancements or Block External To External Transfer Service Parameter), do not upgrade until the Cisco CallManager release that supports the feature becomes available. Otherwise, you will lose the desired functionality and data.
If these features are required at your site, these are possible remedies:
FAC and CMC will not be addressed in Cisco CallManager 4.0, but will be introduced in CallManager 4.1 (which will be released in late 2004).
If you decide that these features are not important, you can upgrade from Cisco CallManager 3.3(4) to 4.0(1), but you lose the 3.3(4) feature-specific data when you upgrade to 4.0(1). After you upgrade to the Cisco CallManager release that provides the features (for example, CallManager 4.1), you must configure the features again if you want to use them with that release.