When I logged in, I opened my inventory, found a few power I bows that were not there previously. When I close and open the inventory again, the inventory becomes full with power I bows. When I throw a bow on the ground, another one takes its place; infinite bows are created. Though, the bows cannot be used; they disappear when right-clicking with the mouse.

I logged out and logged back in. The same issue happened. Though, upon logging in a third time, the issue seemed to resolve itself.

I have since updated to 1.5.2 and the issue seems to gone.