Hm, golfing with GRT? No idea how, but anyway, here's a possible starting point: 
$ perl -le '$,=$/; print @ARGV[ map { unpack N, substr $_, -4 } \
    sort map { eval("v$ARGV[$_]") . pack N, $_ } 0 .. $#ARGV ]' \
    1.2.1.1 1.1.1.1 1.11.1.1 1.1.1.66 1.1.1.9
1.1.1.1
1.1.1.9
1.1.1.66
1.2.1.1
1.11.1.1

[download]
OTOH, that previous version could easily be golfed (ok, just a little) by dropping the initial map (which is useful only when using this snippet "for real" - you know, using sprintf and returning a list): 
$ perl -e 'printf "%vd\n", $_ for sort map { eval "v$_" } @ARGV' \
    1.2.1.1 1.1.1.1 1.11.1.1 1.1.1.66 1.1.1.9
1.1.1.1
1.1.1.9
1.1.1.66
1.2.1.1
1.11.1.1

[download]
--
AltBlue.

In reply to Re^3: How to sort IP addresses by AltBlue
in thread How to sort IP addresses by Anonymous Monk

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