Comment 1 for bug 1100161

Here's a discussion between IRIE Shinsuke(ibus.el maintainer) and an IBus maintainer.
https://code.google.com/p/ibus/issues/detail?id=1419

Based on that discussion it seems like this issue won't be resolved and ibus.el is almost as good as dead.

So are there any other alternatives to ibus-el in emacs?