It might just do what I need in Perl 6, but not in Perl 5.

I have experimented with MIME::WordDecoder. AFAICT in Perl 5 it only allows you to do a destructive mapping onto an 8 bit character set. It loses most of the information and leaves you no way to recreate the original data.

#!/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
[download]

produces

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

Essentially it's just thrown away the KOI8-R characters because they don't map onto ISO-8859, or possibly because it just doesn't understand KOI8-R.

Of course if you can prove me wrong, I would be happy to be corrected. Maybe I just need to invoke it slightly differently?

I've been experimenting with Python 2.3 and it seems much more capable in this area, so I think I'll have to learn another scripting language :-(

$ 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@rrp
+a.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==?=
>>>
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