byte[] DaclByte = (Byte[])DirectoryEntry.Properties["msExchMailBoxSecurityDescriptor"][0];
                System.DirectoryServices.ActiveDirectorySecurity adDACL = new ActiveDirectorySecurity();
                adDACL.SetSecurityDescriptorBinaryForm(DaclByte);

                System.Security.AccessControl.AuthorizationRuleCollection aclCollection = adDACL.GetAccessRules(true, false, typeof(System.Security.Principal.SecurityIdentifier));
                foreach (System.Security.AccessControl.AuthorizationRule ace in aclCollection)
                {

mailboxDirectoryEntry.publicDelegates