From RFC 1521 (the MIME RFC):
Rule #1: (General 8-bit representation) Any octet, except those
indicating a line break according to the newline convention of the
canonical (standard) form of the data being encoded, may be
represented by an "=" followed by a two digit hexadecimal
representation of the octet's value. The digits of the
hexadecimal alphabet, for this purpose, are "0123456789ABCDEF".
Uppercase letters must be used when sending hexadecimal data,
though a robust implementation may choose to recognize lowercase
letters on receipt. Thus, for example, the value 12 (ASCII form
feed) can be represented by "=0C", and the value 61 (ASCII EQUAL
SIGN) can be represented by "=3D". Except when the following
rules allow an alternative encoding, this rule is mandatory.
So that explains it, then. Now how to deal with it? …
By the way, I’ve reverted to my old blog script for entering this post! :)
