install libsqlrelay-ruby python-biopython-martel mird1 med-imaging libginac-dev Building the package cache... W: the release 'http://snapshot.debian.org/archive/debian/20110120T150156Z squeeze' has expired (expiry time 'Thu, 27 Jan 2011 14:17:50 UTC') Initializing package resolver and worker... E: invalid version string '0.78_02-1' W: error while parsing a version for the package 'perl-modules' Scheduling requested actions... Resolving possible unmet dependencies... W: version string 'M17-1': first upstream character 'M' is not a digit W: version string 'M17-1': first upstream character 'M' is not a digit W: some solutions were dropped, you may want to increase the value of the 'cupt::resolver::max-solution-count' option E: unable to resolve dependencies, because of: python-biopython-martel 1.45-3 conflicts with 'python2.3-biopython-martel (<< 1.42-1)' -> no solutions python2.3-biopython 1.30-2 depends on 'python2.3-biopython-martel (>= 1.30)' -> installed python2.3-biopython-martel 1.30-2 python-biopython 1.30-2 depends on 'python2.3-biopython' -> installed python2.3-biopython 1.30-2 python-biopython-martel 1.45-3 depends on 'python-biopython' -> installed python-biopython 1.30-2 python-biopython-martel 1.45-3 depends on 'python-biopython' -> installed python-biopython 1.30-2 E: error performing the command 'install'