Try this.

use strict;
use warnings;
use IO::Compress::Zip qw(:all);


{
    my $zip = new IO::Compress::Zip "/tmp/my.zip", 
                          Name => "foo/bar.txt"
        or die "Cannot create zip file : $ZipError\n" ;

    print $zip "hello world" ;
}

# Check the zip file was created
system "unzip -l /tmp/my.zip" ;
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Here is what I get this when I run that code.

Archive:  /tmp/my.zip
  Length      Date    Time    Name
---------  ---------- -----   ----
       11  09-28-2012 16:44   foo/bar.txt
---------                     -------
       11                     1 file
[download]