A non-regex option:

#!perl -w
use strict;

undef $/;

my $csv = join(',',split(/\n+/,<DATA>));

print $csv;

my @values = split(/,/,$csv); # hmmm, we had this a couple of lines ba
+ck

__DATA__
1
2
3

4

5
6
[download]

It does seem a bit strange to create a new string just with a different delimiter purely so you can split it again. I agree with myocom above - you can split the list straight into an array.

"Argument is futile - you will be ignorralated!"