#!/usr/bin/perl -w
use strict;
use Data::Dumper::Simple;

my %data;

while (<DATA>) {
    chomp;
    my @fields = split /=/;
    my $depth = scalar @fields;
    if ($depth == 1) {
        $data{$fields[0]} = undef;
    }
    elsif ($depth == 2) {
        $data{$fields[0]} = $fields[1];
    }
    elsif ($depth == 3) {
        $data{$fields[0]}{$fields[1]} = $fields[2];
    }
}

print Dumper(%data);

__DATA__
a = ID = 1234
b=Gadens_Melb
c=
d=
e=2006-03-27 15:10:06
f= ContactSensor:INPUT2
g=Critical
h=Event-101 fatal stack error on PRI 001
[download]

Output:

%data = (
          'e' => '2006-03-27 15:10:06',
          'c' => undef,
          'a ' => {
                    ' ID ' => ' 1234'
                  },
          'h' => 'Event-101 fatal stack error on PRI 001',
          'g' => 'Critical',
          'b' => 'Gadens_Melb',
          'd' => undef,
          'f' => ' ContactSensor:INPUT2'
        );
[download]

Cheers,
Darren :)

Here is a recursive solution for an arbitrary depth of hash.

my %hash=();
Define( \%hash, split /\s*\=\s*/ )
    for (split /\n/, $scalar);

sub Define { # value returned not used above,
             # but can be useful for some other cases
    my $href = shift;
    my $key = shift or return $href;
    defined ( $href -> { $key } ) or $href -> { $key } = {};
    my $value = shift or return $href -> { $key };
    @_ and return Define( $href -> { $key }, $value, @_ );
    return $href -> { $key } = $value;
}
[download]

sub hasher { shift(), (@_ ? $#_ ? { &hasher } : @_ : return) }

my %hash;

while (<DATA>) {
        chomp;
        my @a = hasher(split /=/);
        $hash{ $a[0] } = $a[1] if @a == 2;
}

use Data::Dumper;
print Dumper \%hash;


__DATA__
a = ID = 1234 = this is the next bit = fifteen = 19.168.0.2
<<Start of info>>
b=Gadens_Melb
c=
d=
e=2006-03-27 15:10:06
f= ContactSensor:INPUT2
g=Critical
h=Event-101 fatal stack error on PRI 001
[download]

$VAR1 = {
          'e' => '2006-03-27 15:10:06',
          'a ' => {
                    ' ID ' => {
                                ' 1234 ' => {
                                              ' this is the next bit '
+ => {
                                                                      
+      ' fifteen ' => ' 19.168.0.2'
                                                                      
+    }
                                            }
                              }
                  },
          'h' => 'Event-101 fatal stack error on PRI 001',
          'g' => 'Critical',
          'b' => 'Gadens_Melb',
          'f' => ' ContactSensor:INPUT2'
        };
[download]