Unsupported hack or workaround to get 64-bit OS X to install on a MacBook Pro having only 32-bit EFI?

I want to install the 64-bit OS X 10.7 on my MacbookPro 2,1, which has a 64-bit processor, but only 32-bit EFI and Kernel Boot mode. I know that this is not officially supported, but I assume there is some workaround since the hardware provides everything needed to run a 64-bit OS, except for the EFI. "Select Startup Mode" tells me, that: *"While your Mac is technically able to run a 64-bit kernel, this is not currently enabled by Apple."* How can I get that to work? Is there an unsupported hack or workaround?