I'd probably use a hash of hashes, with the outer hash keyed by the ticket id:

use strict;
use warnings;

my @fields = ( 'customer', 'status', 'priority', 'owner' );
my ( %HoH, $ticket );
while ( <DATA> ) {
   chomp;
   next if /^$/;  # Better data validation recommended!
   if ( my @tmp = /
                   ^(\S+):
                   \s+\[([^\]]+)\] # square bracket, followed
                   \s+\[([^\]]+)\] # by anything other than a
                   \s+\[([^\]]+)\] # square bracket, followed
                   \s+\[([^\]]+)\] # by a square bracket
                  /x ) {
      $ticket = shift @tmp;
      $HoH{$ticket} = { map { $fields[$_] => $tmp[$_] } 0 .. $#tmp };
   }
   else {
      s/^\s+//g;
      $HoH{$ticket}{comment} .= " $_";
   }
}

foreach my $record ( keys %HoH ) {
   print "\n$record:\n";
   print "$_ = $HoH{$record}{$_}\n" for keys %{ $HoH{$record} };
}

__DATA__
fabx-t160: [ggurudut] [UNAN/OWNR] [C2] [kelrod]
   navicli chglun -l 3 -name "newname" doesn't work.
   Try a different name, retardo!

fabx-t161: [dozone] [UNAN/OWNR] [C2] [dchoi]
   The GUI needs to hide the CPP SEs from the unimported list
fabx-t162: [haurora] [UNAN/OWNR] [C1] [glade]
   Cisco hardware related bug :idprom error on cisco switch on loading
+ 0.1.5.5
   salagent
[download]

(Code tested, but only on a limited data set)

However, YMMV.

dave