These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild N ~] dev-perl/Class-Singleton-1.400.0 0 kB [ebuild N ] perl-core/Attribute-Handlers-0.930.0 0 kB [ebuild N ~] perl-core/ExtUtils-Manifest-1.610.0 0 kB [ebuild N ] virtual/perl-Attribute-Handlers-0.930.0-r1 0 kB [ebuild N ~] virtual/perl-ExtUtils-Manifest-1.610.0 0 kB [ebuild UD#] dev-lang/perl-5.10.1 [5.12.4-r1] USE="berkdb gdbm -build -debug -doc -ithreads" 0 kB [ebuild U ~] dev-lang/perl-5.16.3:0/5.16 [5.12.4-r1:0/0] USE="berkdb gdbm -build -debug -doc -ithreads" 13,420 kB [ebuild N ] dev-perl/Class-Load-0.06 USE="{-test}" 0 kB [ebuild N ~] virtual/perl-ExtUtils-Install-1.540.0 0 kB [ebuild N ~] virtual/perl-ExtUtils-Command-1.170.0-r3 0 kB [ebuild N ~] perl-core/ExtUtils-MakeMaker-6.640.0 0 kB [ebuild U ~] virtual/perl-ExtUtils-MakeMaker-6.640.0 [6.56] 0 kB [ebuild N ] dev-perl/Params-Validate-1.0.0 0 kB [ebuild N ~] dev-perl/DateTime-TimeZone-1.560.0 USE="{-test}" 0 kB Total: 14 packages (2 upgrades, 1 downgrade, 11 new), Size of downloads: 13,420 kB !!! Multiple package instances within a single package slot have been pulled !!! into the dependency graph, resulting in a slot conflict: dev-lang/perl:0 (dev-lang/perl-5.16.3::gentoo, ebuild scheduled for merge) pulled in by =dev-lang/perl-5.16* required by (virtual/perl-ExtUtils-Command-1.170.0-r3::gentoo, ebuild scheduled for merge) (and 1 more with the same problem) (dev-lang/perl-5.12.4-r1::gentoo, installed) pulled in by ~dev-lang/perl-5.12.4 required by (virtual/perl-libnet-1.220.0-r1::gentoo, installed) (and 11 more with the same problem) (dev-lang/perl-5.10.1::gentoo, ebuild scheduled for merge) pulled in by ~dev-lang/perl-5.10.1 required by (virtual/perl-ExtUtils-Install-1.540.0::gentoo, ebuild scheduled for merge) (and 1 more with the same problem) It may be possible to solve this problem by using package.mask to prevent one of those packages from being selected. However, it is also possible that conflicting dependencies exist such that they are impossible to satisfy simultaneously. If such a conflict exists in the dependencies of two different packages, then those packages can not be installed simultaneously. You may want to try a larger value of the --backtrack option, such as --backtrack=30, in order to see if that will solve this conflict automatically. For more information, see MASKED PACKAGES section in the emerge man page or refer to the Gentoo Handbook. The following keyword changes are necessary to proceed: (see "package.accept_keywords" in the portage(5) man page for more details) #required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =dev-perl/Class-Singleton-1.400.0 ~ppc64 #required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =dev-perl/DateTime-TimeZone-1.560.0 ~ppc64 #required by dev-perl/Unicode-EastAsianWidth-1.320.0, required by app-text/texi2html-5.0-r1[unicode], required by app-text/texlive-2011, required by @selected, required by @world (argument) =virtual/perl-ExtUtils-MakeMaker-6.640.0 ~ppc64 #required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =virtual/perl-ExtUtils-Command-1.170.0-r3 ~ppc64 #required by virtual/perl-ExtUtils-Command-1.170.0-r3, required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =dev-lang/perl-5.16.3 ~ppc64 #required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =perl-core/ExtUtils-MakeMaker-6.640.0 ~ppc64 #required by virtual/perl-ExtUtils-Install-1.540.0, required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =dev-lang/perl-5.10.1 ~ppc64 #required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =virtual/perl-ExtUtils-Manifest-1.610.0 ~ppc64 #required by virtual/perl-ExtUtils-Manifest-1.610.0, required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =perl-core/ExtUtils-Manifest-1.610.0 ~ppc64 #required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) =virtual/perl-ExtUtils-Install-1.540.0 ~ppc64 The following mask changes are necessary to proceed: (see "package.unmask" in the portage(5) man page for more details) #required by virtual/perl-ExtUtils-Install-1.540.0, required by perl-core/ExtUtils-MakeMaker-6.640.0, required by virtual/perl-ExtUtils-MakeMaker-6.640.0, required by dev-perl/DateTime-TimeZone-1.560.0, required by =dev-perl/DateTime-TimeZone-1.560.0 (argument) # /usr/portage/profiles/package.mask: # Torsten Veller (06 Jan 2011) # Next step to remove old perl and libperl versions. # Versions prior 5.12 are masked and will be removed when 5.14 is available. # If you are a sparc-fbsd user and your only keyworded perl version was masked, # test perl-5.12.2 and reply to bug 288028 # For other complaints go to bug 350785 =dev-lang/perl-5.10.1 NOTE: The --autounmask-keep-masks option will prevent emerge from creating package.unmask or ** keyword changes.