OpenCL 1.1 driver (258.19) and the new GTX 5xx series

The old 258.19 driver from June’10 obviously has no support for the new GTX 5xx series.
We are working on the interactive application in OpenCL 1.1 (performance is a key) and we have to fall-back to Fermi because of this issue.
I’ve tried to copy the description for new GPUs from the fresh driver, but it seems like the binaries don’t support it anyway.
Would that be possible to rebuild this driver with support for new GPUs?

Best wishes,
Anton