After I had the initial stuff done, I spent some time yesterday (roughly one hour) figuring out, why Play/Pause/Stop aren’t working any longer (they worked at some point).
After looking at the XBMC debug log for some time, I went back and looked at my Lircmap.xml. As it turns out, you can’t map one Lirckey to two functions (in my case, I mapped KEY_7 to <pause> as well as <seven>). XBMC doesn’t like that, and in return quits functioning for those keys.
After removing the number declarations (<one> through <zero>), my keys are back to working order and I’m completely pleased with my media center Acer 😉