This is a solution. Not very efficient though (sorry)... but I found it interesting.

sub ar_init {
        my $shift = shift ;
        (defined $_[0])
                ? [ map { ar_init(@_) } (1..$shift) ]
                : $shift ;
}

my $array_ref = ar_init(3, 2, 4, 'pop ');

print $array_ref->[2][0][3]
[download]

Since lists are 'flattened' in subroutine calls, you could put the dimensions in an array @dim = (3, 2, 4) and call it using ar_init(@dim, 'foo') - it would have the same effect. Note that the whole thing is constructed using references - you'll need to understand references for whatever solution you use. I like the explanation of reference syntax in _Effective_Perl_Programming_.