yeah
but that happens when i did the recent firmware updated (i had 10.5.5 prior to that, working with "wake on ethernet admin" and still being able to sleep it..)
after firmware update, even by-button sleep didnt work, it went to sleep and woke up again... (hence the original topic name)
after i disabled wake on ethernet it went back to sleep either by menu or automatically, but after 10.5.6 it stopped going to sleep automatically and still works by menu.
and this mac had no sleep issues before