Doing this with a 32-bit only Perl is a tad more complex, but works. You break the 64-bit number into 2 32-bit values and then multiply them out. You do have to pay attention to endianess though.

#! perl -slw
use strict;
use constant {
    MSEpoch_2_UnixEpoch => 116444736000000000,
};

my $in = '0x50c2b17c7c04c9014c69ac817f04c90176b7ed3581f7ca01ee1183dede
+a3c901';

my @hexTimes = unpack 'xx(A16)4', $in;

my @binTimes = map{
    my( $lo, $hi ) = unpack 'VV', pack 'H8H8', unpack 'A8A8', $_;
    $hi * 2**32 + $lo
} @hexTimes;

my @unixTimes = map{ ( $_ - MSEpoch_2_UnixEpoch ) /1e7 } @binTimes;

print scalar localtime( $_ ) for @unixTimes;

__END__
[13:52:05.69]C:\test>845551.pl
Fri Aug 22 17:28:27 2008
Fri Aug 22 17:50:03 2008
Wed May 19 18:29:26 2010
Fri Mar 13 13:23:16 2009
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