Does bitcoin-qt support mining in a pool? I am having difficulty getting guiminer to share a pool with me but if I mine on bitcoin-qt -gen 1 it starts hashing straight away. So I'd like to know if the official bitcoin client supports pooling?
No. Also the hashing implementation in the client is very, very limited. It is not optimized for different architectures AFAIK and does not support any other calculation medium other than regular CPU. That means no GPU, FPGA or ASIC mining. And CPU are extremely slow in comparison with these (see for example Why a GPU mines faster than a CPU).

For this reason the standard Bitcoin GUI client (bitcoin-qt) does not support mining anymore.