Dealing with emails which don't follow RFC also required, of course. Here is good info about such emails: http://cr.yp.to/immhf.html.

But when I say "RFC compliant" I mean support for all possible formats for email addresses, comments in email headers and all things like locale/language/encoding-specific, for example: 

Content-Disposition: attachment;
           filename*0*=koi8-r'ru'%F0%D2%C9%D7%C5%D4
           filename*1*=%20from
           filename*2=" russia.txt"

[download]

And about 'defect free'. There enough information on this topic now. Good example of it is DJB software and most basic&simple *NIX utils. I'm sure: more code == more bugs, so I always prefer smaller/simpler solutions.

I'm sure solution compliant to all these RFC can be coded under ~1000-1500 lines of code (I've partially done it already).

In reply to Re^2: Reliable email parsing by powerman
in thread Reliable email parsing by powerman

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