Originally posted by Shard O'Glase
Also I happen to let multiple materials be put together with this spell. I think the wording is fairly imprecise and vague, and I'd rather say sure to this, than having to make decisions left and right on what objects are made of only one material and what objects are made up of multiple materials.
If you could make a bridge with Wall of Stone, I think you should be able to do it with Fabricate as one solid material, assuming you have enough material. As far as multile materials, I don't think this spell allows for that. From the SRD:
The character converts material of one sort into a product that is of the same material
Once again, I don't think that it is too much to alter the spell description, but I would think of it as more of a house rule, not an interpretation of the actual spell.