Current default for http://www.postfix.org/postconf.5.html#smtp_line_length_limit
is == 998, per smtp std. Ages ago, Sendmail added an errant "!", causing overruns -- I think that's in part why the prior Postfix value == 990? to accommodate 'broken' Sendmail? Time's passed, clearly the Postfix default has been raised to ==998, but ... has Sendmail actually been fixed to be 998-char compliant? And, in wide enough real-world deployment to be an acceptable risk? Or is the real-world recommendation still to dumb-down to == 990?
