I understood what you ment, just got the terms mixed up (again).
That PAE for the OS is a pain in the ass, but a patch to make an application large address aware shouldn't be problematic.
Games are starting to push the memory barrier, especially sims. Some, like DCS A-10C, moved to 64-bit because of it. Wish more developers would make the step, they're going to have to at some point.