Application-specific keymapping

Question

In general, I want to make specific keymaps for application, that working only in it and doesn't affect any other app.

For example, I already use my Caps key to toggle input language (via xorg.conf), but I want Capslock to behave like Esc in vim. Looks like xmodmap doesn't have any options related to that.

I use Gnome and would also appreciate any third-party applications.

Answer 1

I found solution in evrouter. It maps any keyboard event onto keypress in X.Org if active window title is matched by regexp you specify. It also helps me to deal with Zoom key on my Microsoft Natural Keyboard.
The bad thing is default X keypress also occurs.