#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;

my $sep    = '<;>';
my $string = 'a<;>eine<;>an<;>eine<;>one<;>eine<;>to have a smoke<;>eine rauchen [ugs.]<;>';
my @info   = split /$sep/, $string;

my @array;
while( @info ){
    push @array, [shift @info, shift @info];
}

print Dumper \@array;