Created attachment 91079 [details]
screenshot of charset bug

The first thing I'd recommend is to upgrade your GMime library, which does a lot of the charset work for Pan.  The newest version of GMime is 2.13.7.

Please let me know if upgrading GMime doesn't solve the problem.

Sorry, but where I can download gmime 2.13.7 ? According to ftp.gnome.org I`ve got  latest Gmime 2.2.10.

I'm sorry, 2.2.10 /is/ the latest version.  I'm not sure how I managed to get the wrong number there.

List of libs pan depends on:

ii  aspell                  0.60.5-1         GNU Aspell spell-checker
ii  libaspell15             0.60.5-1         GNU Aspell spell-checker runtime l
ii  libatk1.0-0             1.18.0-2         The ATK accessibility toolkit
ii  libc6                   2.6-5            GNU C Library: Shared libraries
ii  libcairo2               1.4.10-1+b2      The Cairo 2D vector graphics libra
ii  libfontconfig1          2.4.2-1.2        generic font configuration library
ii  libgcc1                 1:4.2.1-1        GCC support library
ii  libglib2.0-0            2.12.13-1        The GLib library of C routines
ii  libgmime-2.0-2          2.2.10-1         MIME library, unstable version
ii  libgtk2.0-0             2.10.13-1        The GTK+ graphical user interface 
ii  libgtkspell0            2.0.10-3+b1      a spell-checking addon for GTK's T
ii  libpango1.0-0           1.16.5-1         Layout and rendering of internatio
ii  libpcre3                6.7-1            Perl 5 Compatible Regular Expressi
ii  libstdc++6              4.2.1-1          The GNU Standard C++ Library v3
ii  libx11-6                2:1.0.3-7        X11 client-side library
ii  libxcursor1             1:1.1.8-2        X cursor management library 
ii  libxext6                1:1.0.3-2        X11 miscellaneous extension librar
ii  libxfixes3              1:4.0.3-2        X11 miscellaneous 'fixes' extensio
ii  libxi6                  2:1.1.2-1        X11 Input extension library
ii  libxinerama1            1:1.0.2-1        X11 Xinerama extension library
ii  libxrandr2              2:1.2.1-1        X11 RandR extension library
ii  libxrender1             1:0.9.2-1        X Rendering Extension client libra
ii  zlib1g                  1:1.2.3.3.dfsg-5 compression library - runtime

Did you set the group's charset before or after downloading those headers ? Try deleting all headers and downloading them again now that you've set the charset.

> Try deleting all headers and downloading them again now that you've set the charset.

It doesn`t help. 

Confirm.
Have same bug in private newsgroup.
Postings in this group are koi8-r, cp-1251 and Unicode charsets.

If message have encoding settings in headers section - header looks fine.

Example:
User-Agent: XanaNews/1.18.1.6
MIME-Version: 1.0
Content-Type: text/plain; charset=koi8-r
Content-Transfer-Encoding: 8bit

I think that Pan uses unicode charset in headers instead of default body charset (i set KOI8-R in View-body pane). 

Some headers of postings of Outlook Express 6 messages haven't message charset info. In this case I see transcoded trash in headers.

Example of trash-headed message

From: "user" <*****@mail.ru>
Newsgroups: sochi.talk
References: <4afd50d2@news.sochi.ru> <4afd5190$1@news.sochi.ru>
Subject: Re: Власти Москвы намерены построить 24 подводные парковки
Date: Fri, 13 Nov 2009 15:26:11 +0300
Lines: 6
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 6.00.2900.3138
X-RFC2646: Format=Flowed; Response
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138
X-Antivirus: avast! (VPS 091112-1, 12.11.2009), Outbound message
X-Antivirus-Status: Clean
NNTP-Posting-Host: ***.***.***.***
Message-ID: <4afd525e$1@news.sochi.ru>
X-Trace: news.sochi.ru * *.*.*.* (13 Nov 2009 15:34:38 +0400)
X-Authenticated-User: *
Path: news.sochi.ru!not-for-mail
Xref: net sochi.talk:51951

<message body here>

This problem has been fixed in the development version. The fix will be available in the next major software release. Thank you for your bug report.