Post Slug: ignored?

When initially creating a post, if I enter a one word post slug, and click publish, the slug is ignored in favor of the dirified title. Same thing happens if I save, then go to edit the draft�the post slug field is populated with the much longer value.
However, if I go back–once the post is published–and overwrite the post slug value a second time, it sticks. So basically there is a workaround but it sure ain’t slick.
Anyone else noticing this behavior?
Using 1.2-epsilon-RC1.