Wrong Still/Freeze Durations

So I go to set up a new project into which I'll be importing folders of stills. I set the default Still / Freeze Duration for 5 seconds and import my first folder of clips. They come in with a duration of 4 seconds. If I set the duration for 6, then I get my desired 5 seconds. I'll go with the work-around for now, but something's wrong. Any thoughts?

And yes, I trashed prefs.

FCP 5.1.1
OS 10.4.7
MacPro 2x2.66

Check to make sure your sequence preset (under audio/video settings) matches the framerate of your timeline. This used to be a problem for me, although I haven't run into with 5.1.1 or 5.1.2.