Pallet Loading

What is the complexity of the pallet loading problem? Given two pairs of numbers, $(A,B)$ and $(a,b)$, and a number $n$, decide whether $n$ small rectangles of size $a \times b$, in either axis-parallel orientation, can be packed into a large rectangle of size $A \times B$.

This problem is not even known to be in NP, because of the compact input description, and the possibly complicated structure of a packing, if there is one.