# open your file 1 as $IN1...
my %hash_file_1;
while (<$IN1>) {
     if (/entry) {
          my $key = $_;
          my $value = "";
          while (<$IN1>) {
              last if /EOE/;
              $value .= $_;
          }
          $hash_file_1{$key} = $value;
     }
}
# open file 2 as $IN2
while (<$IN2>) {
     if (/entry) {
          my $key = $_;
          if (exists $hash_file_1{$key}) {
               my $value2 = "";
               while (<$IN2>) {
                    last if /EOE/;
                    $value2 .= $_;
               }
              # do the comparison between $value2 and $hash_file_1{$key}
              # and print what you need
          }
     }
}