Armor secret in map 08

Hi! Can anybody help with the armor secret in map 08? I cannot find a way to grab the armor. Jumping into the niche is not possible, and shooting on everything near the niche did not produce any results. I checked with Doom Builder, but I'm still at a loss. TIA Ulrich

prboom -playdemo armorjump

http://ftpusers.coffeenet.org/~cato/freedoom/demos/armorjump.lmp

Of course, this is the only way to jump, should have thought of that by myself -- thanks! Ulrich