A quick follow-up: The only place my configuration differed from idealist's was on the Sharing tab of the Bluetooth page in System Preferences. Two of the three checkboxes under the 'key' icon weren't ticked on my laptop.
To test, I ticked those boxes, then tried connecting via my Pearl. I was able to successfully connect and disconnect three times without pulling the battery! However, the fourth time the phone once again wedged itself and required a battery pull to fix the problem.
So, it seems as though ticking the checkboxes makes a difference, even if it doesn't completely remove the problem. Further investigation needed.