Linux hovering: should it work?

Should hovering over a word make it get looked up? I don't see a preference for this, and under Linux (Ubuntu 13.10, 64-bit, using xmonad; goldendict 1.5.0+git from the official Ubuntu repository), words never get looked up no matter how long I hover. I'd like to be able to use goldendict as a mouseover dictionary tool.
Single/double-click lookups and modifier keys work, and I have scan popup enabled; it's just hovering which isn't doing anything. Judging by the source code and other threads, it seems to work on at least some platforms: should it also already be working on mine, or am I overlooking something?
Single/double-click lookups and modifier keys work, and I have scan popup enabled; it's just hovering which isn't doing anything. Judging by the source code and other threads, it seems to work on at least some platforms: should it also already be working on mine, or am I overlooking something?