Extrusion, bent box


I want to create a bent box in jME

After many different attempts, now i am trying with an Extrusion of a rectangle along a bent line

that works fine for one line, it generates a bend area… but when i create a rectangle consisting of 4 lines and try to extrude this, i get very weird results…, i assume a should get a bent box but i get a lot of strange looking areas :wink:

has anybody an idea how to create such an object?

thanks and greets