#!/usr/local/bin/perl5.8.5

use strict;
use MIME::WordDecoder;

my $field='From: =?koi8-r?B?7s/Xb2PUdSDT1NLBeG/Xwc7J0Q==?= <m2z19uyn1b@rrpa.com>';
my $decoded = unmime( $field );
print $decoded

##</code><code>##

./decode.pl
ignoring text in character set `KOI8-R'
 at ./decode.pl line 7
From: 1 <m2z19uyn1b@rrpa.com>

##</code><code>##

$ python2.3 
Python 2.3.4 (#1, Aug  3 2004, 16:01:36) 
[GCC 2.96 20000731 (Red Hat Linux 7.3 2.96-110)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from email.Header import Header
>>> from email.Header import decode_header
>>> h='From: =?koi8-r?B?7s/Xb2PUdSDT1NLBeG/Xwc7J0Q==?= <m2z19uyn1b@rrpa.com>'
>>> decode_header( h )
[('From:', None), ('\xee\xcf\xd7oc\xd4u \xd3\xd4\xd2\xc1xo\xd7\xc1\xce\xc9\xd1', 'koi8-r'), ('<m2z19uyn1b@rrpa.com>', None)]
>>> h = Header('\xee\xcf\xd7oc\xd4u \xd3\xd4\xd2\xc1xo\xd7\xc1\xce\xc9\xd1', 'koi8-r')
>>> print h
=?koi8-r?b?7s/Xb2PUdSDT1NLBeG/Xwc7J0Q==?=
>>>