Same here,
ended wars with UP resolution, it also says no wars can be declared for some time. But it passed and I declared war the next turn on some other race.
Weird. It does not seem to be consistant. I remember that happenning with one of the beta, but I just tested it last night. Got myself elected, made the proposition, had it pass and the war with the Altarians I was engaged in stopped the next turn. And I couldn't declare war during this time.
We will have to investigate. Maybe it works if you are the one proposing the resolution? That would be the bug...