To  change  from   digest  to  regular  mail   delivery,  the  officially
recommended syntax is  SET NODIGEST. This will work on  all versions. SET
MAIL will  also work. Prior to  1.8b, MAIL and NODIGEST  are synonyms. In
1.8b, SET MAIL acts as SET MAIL NODIGEST when you were not set to NOMAIL,
for compatibility.
 
  Eric