I have a MCV Vera (primary Z-wave controller to LinuxMCE as secondary controller), and this is a relatively easy thing to do with that system (and can be very easily integrated as a primary controller to LinuxMCE's secondary controller, or vice versa, depending on what you want to do). Any similar "smart" Z-wave controller should be able to accomplish the same thing. What you would need would be a Wayne Dalton Wayne Dalton WDHA-12R - Wireless Gateway Module ($65 USD) and one or more Dalton KEP-IV - 372 Mhz Wireless Keypads ($40 USD). As for smart controllers, the most economical is the MCV Vera Lite ($179 USD). There's also a keychain fob that can talk to the system through the Wayne Dalton gateway. That's the easy way to do this sort of thing, without twisting LinuxMCE functions around to try and accomplish the same thing.
As for LinuxMCE doing it,... You'd want to use environmental or security settings to accomplish something similar,... But as Posde indicated, there's not really anything there for detected keypress combinations. I don't know if LinuxMCE can even respond to the Wayne Dalton gateway/keypad gear. The idea in LinuxMCE is for the environment to respond automatically to usage cases, like watching a movie in the living room in the evening (vs. daytime), setting away from home settings, Moving from one room to another, and having conditions follow you there, etc. I use the smart controller functions if the Vera for the kind of stuff that you're talking about.