#! perl -slw
use strict;

print map{ 
	$_->[0] 
} sort { 
	$a->[1] cmp $b->[1] 
} map {
	( my $vstring = $_ ) =~ s[(\d+)][chr $1]ge;
	[ $_, $vstring ]
} <DATA>;

__DATA__
a1.5
a1.55
a1.55b
a1.5b
a1.6
a1.6b
linux-2.10.50.tar
linux-2.10.6.tar
linux-2.4.28.tar
linux-2.4.29.tar
linux-2.4.29a.tar
linux-2.4.3.tar