UBB.threads PHP Forum Software Community Forums UBB.threads 7 Bug Reports Non Bugs 7.3 Galley subforums - bug?

Not sure if this is a bug, or by design. Today I tried to create a gallery sub-forum within an existing gallery and found I could not. It acts like it is creating the forum, but the forum never appears anywhere. Is this a bug, or are gallery forums not able to have gallery sub-forums by design?