Many thanks !
I'm still in office,
i'll try to fix the cookies with you help site when i come back home
If it will be fast and easy it could be acceptable even for the users ...
But anyway i think it would be better to be able choose a special name for cookies files,
so old cookies would be just ignored,
if you change cookies prefix after changing domain back
( i think there was another forum software, that had this option by default in admin...

)
So i still hope, anyone from Dev Team respond too...
Oh, and by the way - may i copy your help post/thread
to my forum or my site ?
Burns