Hooray,
just sent a SMS with an iPhone emoticon -that did not work before- from N900 to N9 (and vice versa with some added harmoji 0.6.6)!

Thanks thp (and hedayat).

--edit
just one (maybe) negative thing now:
the char counter is f*#cked up
on N900 it goes immediately from 160 to 67 after inserting an emoticon (which is pretty normal)
and/but also jumps from 160 to 68 on inserting a normal character
--edit
and goes back to 158 after inserting second ASCII character. So, as I assume, no one will send a one-char SMS all good on N900

on N9 the counter goes to zero on inserting an emoticon

no idea whether those counters are reliable now (possibly using utf16 'eats' resources, 92 chars????)