Process substitutions MTA option

Direct LDAP attribute interpretation MTA options:  (bit-encoded integer)
New in MS 6.3. The  MTA option controls  whether to process substitution sequences in the URL values of various LDAP attributes. See Table of LDAP URL substitution sequences for a list of substitution sequences (though only some such substitution sequences make sense and are available in the contexts discussed below). The default is 0, meaning that all such substitutions are disabled by default.

Bit 0 is the least significant bit.

Note that the information source for substitution values varies depending on whether the attribute in question is used for authorization checks, or for actual list expansion. For authorization attributes, the whole address, domain , host , and local-part are all derived from the authenticated sender address. In the case of list expansion attributes, all of these substitution values are derived from the envelope recipient address that specified the list. In both cases, however, the subaddress substitution is derived from the current envelope recipient address.

In particular, the ability to access subaddress information in list expansion URLs makes it possible and convenient to define a "meta-group"; that is, a single group entry that in effect creates an entire collection of different groups. For example, a group with attributes including: mail: group@domain.com mgrpDeliverTo: ldap:///o=usergroup?mail?sub?(department=$S) would make it possible to send mail to every member of a given department with an address of the form group+department@domain.com Note that creation and use of such a "meta-group" does not require the use of subaddresses (though subaddresses are often a convenient syntax for such a purpose). Other mechanisms, such as other forms of "special" addresses transformed via a   mapping table  or     attribute&#x27;s value  mapping table, could be used instead to provide "meta-group" functionality. Note that  effects, if any, occur after the   table, if any, has been applied.

See also:
 * Direct LDAP attribute interpretation MTA options
 * LDAP URL substitution sequences
 * ldap_cant_url MTA Option
 * ldap_auth_url MTA Option
 * ldap_moderator_url MTA Option
 * ldap_group_url1 MTA Option
 * ldap_group_url2 MTA Option
 * ldap_errors_to MTA Option
 * ldap_jettison_url MTA Option
 * FORWARD mapping table
 * ldap_url_result_mapping MTA Option