Microsoft made changes to their Windows Live Messenger servers on November 8 2011 which negatively impacts the ability of instant messenger clients (Kopete, emesene to name a couple) using libmsn 4.1 and earlier to connect.

At the time of writing version 4.2 addresses the issue but is not included in the mainstream portage for Gentoo. We will use an ebuild from the KDE overlay available at http://gpo.zugaina.org/net-libs/libmsn/euscan to implement a quick and dirty fix without setting up the whole overlay. It will not survive the next emerge --sync but I am operating on the expectation that 4.2 will be brought mainstream ASAP due to demand.

Note that we must comment the PATCHES line:

# Copyright 1999-2010 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: $

EAPI=4

inherit cmake-utils

DESCRIPTION="Library for connecting to Microsoft's MSN Messenger service."
HOMEPAGE="http://sourceforge.net/projects/libmsn/"
SRC_URI="mirror://sourceforge/${PN}/${P}.tar.bz2"

LICENSE="GPL-2"
SLOT="0"
KEYWORDS="~alpha ~amd64 ~hppa ~ia64 ~ppc ~ppc64 ~sparc ~x86 ~amd64-linux ~x86-linux"
IUSE="debug"

DEPEND="
        dev-libs/openssl
"
RDEPEND="${DEPEND}"

DOCS=(README THANKS TODO)

#PATCHES=( "${FILESDIR}/${P}-install-xmlparser-header.patch" )

Download the bzipball to /usr/portage/distfiles:

# wget http://ufpr.dl.sourceforge.net/sourceforge/libmsn/libmsn-4.2.tar.bz2

Digest the ebuild (yum!):

# cd /usr/portage/net-libs/libmsn
# ebuild libmsn-4.2.ebuild digest

Now unmask 4.2:

# echo "net-libs/libmsn" >> /etc/portage/package.keywords

Emerge the new version of libmsn:

# emerge --update libmsn

Now restart your libmsn dependent instant messenger.