choosing an option from the Places menu spawns x instances of Nautilus

Binary package hint: nautilus

Since upgrading to Edgy, both my PCs have experienced this problem. My two systems appear to be the only two affected, and I have no idea how to reproduce this on other systems.

Steps to reproduce:
1. Select a location on the places menu.

What should happen:
  The selected location should appear in a Nautilus browser.

What happens:
  Sometimes the selected location will appear in the Nautilus browser.
  Occasionally the system will hang as if the location can't be found. Five to ten seconds later, a variable number (usually five to ten) of nautilus browsers will start across the desktop.