I've been looking into this a bit more and I haven't experimented with this yet but it looks like it's possible to have keys behave differently when in different parts of XBMC so that the default behaviour is Numbers and only when your in the Video menu does it switch to Jump SMS type behaviour.
More info here, look at the An Example section towards the bottom which shows how to make the Info key display ingo globally but the OSD when in Full Screen Video mode.
As I say, I haven't experimented with this myself.