How to input Japanese in minibuffer of Emacs by canna

[wen@japan.email.ne.jp]

Hi,
I could not search any Japanese character in Emacs by C-s while
the mode of input method is japanese-canna. When I try to input
a Romanji letter the minibuffer shows "Failling I-search []: "and
the Romanji does not transfer to any Kanji in minibuffer.
My Japanese environment is set by language-env. Thanks!

Regards,

--Wen
wen@japan.email.ne.jp