"Other Amount" contribution field causing an error

Just created the contribution page here: http://sandbox.civicrm.org/civicrm/contribute/transact?reset=1&action=preview&id=4

It's "Testing Other Field Error"

You'll notice that when you select the donation amount "$0.00" you are given an error in the other field. When the other field is not present it works.

It's necessary to have the "other amount" listed for obvious reasons, along with a zero dollar amount so that people can, for instance, sign a petition without requiring a contribution.