ifupdown: dhcp behaviour does not comply with RFC 3442

Under "Additional info" I mentioned the behaviour of network-manager. I tried to reproduce, but now "Classless Static Routes" (option 121) is in effect and "Router" (option 3) is not.

The behaviour with ifup/ifdown and dhclient however didn't change.

Will wait for this to be fixed in Debian, then merge the upload.

This bug was fixed in the package isc-dhcp - 4.2.4-1ubuntu1

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isc-dhcp (4.2.4-1ubuntu1) quantal; urgency=low

  * Merge from Debian. Remaining changes:
    (LP: #768171, LP: #841182, LP: #881558, LP: #872929, LP: #616809)
    - Use upstart jobs for isc-dhcp-server and isc-dhcp-relay.
    - Add IPv6 support to udeb dhclient-script (forwarded as Debian #635897).
    - Add an apport hook to isc-dhcp-client and isc-dhcp-server.
    - Add an apparmor profile to isc-dhcp-client and isc-dhcp-server.
    - Update default dhclient.conf to ask for IPv6 configuration.
    - Patches:
      + dhclient-fix-backoff
      + dhclient-more-debug
      + dhclient-onetry-call-clientscript
      + dhclient-safer-timeout
      + dhcpd.conf-subnet-examples
      + multi-ip-addr-per-if
      + onetry_retry_after_initial_success
      + revert-next-server
  * Set fqdn.fqdn to the result of gethostname(); (LP: #991360)
  * Replace old droppriv and deroot patches by use of --enable-paranoia
    and matching -user and -group parameters to dhcpd. (LP: #727837)
  * Allow read access to /etc/dhcp/ddns-keys/* for ddns. (LP: #341817)
    It's expected that people generate one key per zone and have it stored
    in both /etc/bind9 and /etc/dhcp/ddns-keys/ for security reason.
  * Fix apport hook to work with python3.

isc-dhcp (4.2.4-1) unstable; urgency=low

  * New upstream release
  * debian/control: reformatted Uploaders so that dch doesn't think I'm making
    NMUs
  * debian/rules: do a clean between the LDAP-enabled build and the
    non-LDAP-enabled one, so that no LDAP-related artefacts are accidently
    incorporated into the non-LDAP build
  * debian/dhclient-script.*: conditionalise the chown/chmod of the new
    resolv.conf on the existence of the old one (closes: #595400)
  * debian/dhclient-script.linux: comply with RFC 3442 and ignore
    the routers option if the rfc3442-classless-static-routes option is present
    (closes: #592735)
  * debian/dhclient-script.kfreebsd: fix subnet mask handling (closes: #677985)

isc-dhcp (4.2.2.dfsg.1-5) unstable; urgency=medium

  [ Andrew Pollock ]
  * debian/dhclient.conf: send the hostname (closes: #151820)

  [ Michael Gilbert ]
  * Fix cve-2011-4868: error in DDNS handling with IPv6 (closes: #655746)
  * Fix cve-2011-4539: error in regular expression handling
    (closes: #652259)
  * Make dependencies diff-able
  * Add myself to uploaders
  * Remove all automatically generated files in clean rule
  * Medium urgency for security updates

isc-dhcp (4.2.2.dfsg.1-4) unstable; urgency=low

  * The "Zoe woke up at 4am and I couldn't get back to sleep so I had some
    extra time to work on this" release
  * patch the Makefile for the embedded BIND libraries so that autoconf is run
    so that the modification to configure.in to fix the FTBFS on kFreeBSD
    actually does something useful (closes: #643569)

isc-dhcp (4.2.2.dfsg.1-3) unstable; urgency=low

  * debian/control: remove transitional packages
  * debian/rules: apply the intent of Pierre Chifflier's patch to enable
    hardening options (closes: #644413)
  * debian/control: also add inetutils-ping to the dependencies for
    isc-dhcp-client on hurd (...