Sieve addtag extension

The MTA&#x27;s private Sieve extension  action has been supported  since MS 6.0. provides a convenient way to add a prefix string, that is, a "tag", to a Subject: header line. (The   action  provides  an alternate, though somewhat more complex, mechanism to get such an effect.) Note that the   effect is not visible to other Sieves being evaluated at the same time; this is unlike   (as of MS 6.1p1 and 6.2).

Adding multiple tags is supported, for instance, " " and " ". Prior to MS 6.3,  took a space-delimited list of arguments; as of MS 6.3,   takes a string argument consisting of vertical bar delimited tags. Each of the tags is searched for separately in the current Subject: line, and then added if not already present. (This means in particular that prior to MS 6.3, doing an   operation on a Subject: field that itself includes spaces, e.g.,   on a SpamAssassin verdict, was  not a good idea: "weird" results were possible when part of the tag string was already present on the Subject: header line.  This motivated  the change to use of a vertical bar delimiter for MS 6.3.)

The  Sieve action effect is analogous to the effects of the   alias option, the   alias file named parameter, or the   group LDAP attribute (more precisely, the LDAP attribute named by the   MTA option).

See also:
 * Sieve editheader extension
 * alias_tag Option
 * Alias file named parameters
 * ldap_add_tag MTA Option
 * Sieve filters
 * Sieve supported extensions