[bug:trunk] marshal changes ["foo", "bar", "bar"] to ["foo", "bar", "EUC-JP"]

e$B0J2<$N$h$&$K!"e(B
[“foo”, “bar”, “bar”] e$B$re(B marshal e$B$7$?$O$:$,!"e(Bunmarshal
e$B$9$k$He(B
[“foo”, “bar”, “EUC-JP”] e$B$,=P$F$-$^$9!#e(B

% ./ruby -ve ’
o = [“foo”.force_encoding(“EUC-JP”)] + [ “bar” ] * 2
p o
m = Marshal.dump(o)
p Marshal.load(m)’
ruby 1.9.2dev (2010-02-11 trunk 26640) [i686-linux]
[“foo”, “bar”, “bar”]
[“foo”, “bar”, “EUC-JP”]