Aliases implies mail aliases is a one or more email addresses that are referenced a single name.

Field explanation:

groupName:mgrpRFC822MailMember,mgrpRFC822MailMember,mgrpRFC822MailMember...mgrpRFC822MailMember

Example:

administrator:root

newsadm:        news,user1,user2,user3,...userx
newsadmin:      news
usenet:         news
ftpadm:         ftp
ftpadmin:       ftp
ftp-adm:        ftp
ftp-admin:      ftp
hostmaster:     root

LDAP Fields:

cn:mgrpRFC822MailMember,mgrpRFC822MailMember,mgrpRFC822MailMember...mgrpRFC822MailMember

NOTE: cn and mail should be populated with the same value within the mailGroup objectclass