Most of the libraries from Harmattan are already existing in Maemo 5 or can easily be ported/updated so the only obstacle to execute Harmattan binaries should be the hardfp (and maybe thumb?) requirements.

Maybe it's a silly question but, does anybody know if it would be possible to emulate via software the hardfp needed to execute Harmattan applications in the N900?

To me it sounds like the i387 support that was emulated in the Linux kernel many years ago for computers that didn't have a coprocessor.

Anyone with a deeper knowledge of that?