regression test on a FreeBSD box with both non-MULTIBYTE and
MULTIBYTE-enabled, and confirmed that the results are same.

However I do not tested on PCs(I don't have access to win). Please let
me know if the patches break anything on PCs.

Also please note that the patch for varchar.c is a fix for a nasty bug
of char(n) types that I introduced and I believe at least this should
be applied.

Tatsuo Ishii