@Tjaoz,
Why do you flame others for not understanding your replies, when you clearly don`t understand them?
This is a HARDWARE feature that eFlash 4000 FlashROM memory area is available in the processor data and program space. This allows preparation of such programs/procedures, which may be executed directly in the Flash memory
Executed directly in the flash memory?

That`s dangerous. As others have pointed out, the majority of programs **MUST** be loaded into RAM before execution.
What would happen if the program contained a BSS hunk (and there`s at least one in the 3.9 RomUpdate that does) and was executed directly in flash?
The program stored after it in flash would get overwritten and corrupted.
So either you`re wrong and don`t understand how programs are loaded an run, or you`re right but the eFlash is likely to keep corrupting it`s contents.
BTW, care to explain what you mean by "processor data and program space"