$ sudo aptitude install perl-base:i386
The following NEW packages will be installed:
perl-base:i386{b}
0 packages upgraded, 1 newly installed, 0 to remove and 300 not upgraded.
Need to get 1133 kB of archives. After unpacking 4895 kB will be used.
The following packages have unmet dependencies:
perl-base : Conflicts: perl-base:i386 but 5.18.2-2ubuntu1 is to be installed.
perl-base:i386 : Conflicts: perl-base but 5.18.2-2ubuntu1 is installed.
Unable to resolve dependencies! Giving up...
The following NEW packages will be installed:
perl-base:i386{b}
0 packages upgraded, 1 newly installed, 0 to remove and 300 not upgraded.
Need to get 1133 kB of archives. After unpacking 4895 kB will be used.
aptitude failed to find a solution to these dependencies. You can solve them yourself by hand or type 'n' to quit.
The following packages have unmet dependencies:
perl-base : Conflicts: perl-base:i386 but 5.18.2-2ubuntu1 is to be installed.
perl-base:i386 : Conflicts: perl-base but 5.18.2-2ubuntu1 is installed.
Resolve these dependencies by hand? [N/+/-/_/:/?] n
Abort.
Didn't happen.
$ sudo aptitude install perl-base:i386
The following NEW packages will be installed:
perl-base:i386{b}
0 packages upgraded, 1 newly installed, 0 to remove and 300 not upgraded.
Need to get 1133 kB of archives. After unpacking 4895 kB will be used.
The following packages have unmet dependencies:
perl-base : Conflicts: perl-base:i386 but 5.18.2-2ubuntu1 is to be installed.
perl-base:i386 : Conflicts: perl-base but 5.18.2-2ubuntu1 is installed.
Unable to resolve dependencies! Giving up...
The following NEW packages will be installed:
perl-base:i386{b}
0 packages upgraded, 1 newly installed, 0 to remove and 300 not upgraded.
Need to get 1133 kB of archives. After unpacking 4895 kB will be used.
aptitude failed to find a solution to these dependencies. You can solve them yourself by hand or type 'n' to quit.
The following packages have unmet dependencies:
perl-base : Conflicts: perl-base:i386 but 5.18.2-2ubuntu1 is to be installed.
perl-base:i386 : Conflicts: perl-base but 5.18.2-2ubuntu1 is installed.
Resolve these dependencies by hand? [N/+/-/_/:/?] n
Abort.
System: Xubuntu 14.04.
So...?