Supporter Plugin: Problems with HTML in preferences

I'm using WPMU 2.8.2 and the latest Supporter plugin. I seem to be having an issue with HTML escaping in any preferences which include HTML. For example, my "Supporter feature message" is set up as this:

This feature is limited to supporters only. Click here to find out how to become a supporter.

Once I save and come back to the page, however, my message is now:

This feature is limited to supporters only. Click here to find out how to become a supporter.

Every time I save the preferences, whether I edit the field or not, each quote grows by an extra backslash. So eventually I end up at:

This feature is limited to supporters only. Click here to find out how to become a supporter.

Any ideas on what's going on or what I can do to fix this? Thanks!