Resource types

I'm running v1.9.3+ (20081204) on my production server and have created new course instances based on ones built over the past 3 years (up to and including 1.8).

I'm running into a major problem with some the resource pages that call external web pages-- instead of the 3-option dropdown list for "Keep page navigation visible on the same page," I just get a single checkbox.

I have the 1/21/09 build installed locally for testing and these pages have the full dropdown.

Any ideas? Is this a difference between build numbers, or is it related to course instances imported from prior versions, or ???

I've attached screen grabs from both versions...

Thanks!