Encoding problem with reply to a List or to Sender

Can you be more specific? Do you see any error messages when running Postler from a console and doing this?

And, if this is not sensitive information, could you share the From, To, CC and List-Post headers found in the message source? Accessible via right-click, View Source.

Yes: I run postler from last build: ./waf build --run in general I can see this on the terminal (when I use reply button):
** (postler-compose:2714): WARNING **: Invalid field "from" was ignored.

** (postler-bureau:2657): CRITICAL **: postler-messages.vala:430: parse_address: assertion '!address.length < 1' failed

and it works (: I see the window to reply), but for some mail I receive this (on terminal):
** ERROR **: Failed to parse command line: Sequenza di byte non valida nell'ingresso per la conversione
aborting...

This looks to be an encoding problem, it doesn't happen if I manually remove the body from an affected message.

Broken encoding when replying.
In response to the encoded message windows-1251, quoted text is not readable, you need to remove and insert by hand from the original letter.

postler_0.1.1+r746-0~natty1_amd64.deb (PPA-dev)
libwebkitgtk 1.3.12
locale: LANG=ru_UA.UTF-8
Ubuntu Linux ~11.04