The simplest way is to split the input string and use Date::Manip::ParseDate recursively on resulting array, as it does exactly what you need, i.e. removes the part containing date from the beginning of input without any knowledge about the format.

Example: 

#!/usr/bin/perl

use warnings;
use strict;
use Date::Manip qw(); # I strongly recommend version 5.54

our $TZ = 'GMT'; # to avoid error message

while (<DATA>) {
    s/(-!-)/ $1/;   #to deal with strange comment format
    my @line = split /(\s+)/;
    1 while (Date::Manip::ParseDate(\@line));
    $_ = (join "", @line) || "\n";
    print;
}

__DATA__
09:12: 5:14:29-!- {more garbage goes here} 
09:12: 5:14:37 
09:12: 5:14:37
2008-12-12 00:39 * {more stuff here}
2008-12-12 01:17 < {data here}
2008-12-12 01:30
2008-12-12 01:31

[download]
However, you need to test this method on all types of your data to check if it 'eats' all your bizarre date formats.

In reply to Re: Parsing arbitrarily-formatted timestamps out of log file entries by Ieronim
in thread Parsing arbitrarily-formatted timestamps out of log file entries by mr_flea

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