Andres Salomon uploaded new packages for apache2 which fixed the
following security problem:
CVE-2011-3348
Possible denial of service in mod_proxy_ajp if combined with
mod_proxy_balancer.
For the lenny-backports distribution the problem has been fixed in
version 2.2.16-6+squeeze4~bpo50+1.
For the stable distribution (squeeze), this problem has been fixed
in version 2.2.16-6+squeeze4.