Membership form with optional/additional donation doesn't work if no additional donation is made

This bug is posted here at the request of Lobo.

Ran into a little snag while trying to set up a combination signup/contribution page.
Our goal is that the page does two things:

1) Requires a membership and processes the membership fee
2) Provides the OPTION of making an additional non-membership contribution

We have configured this form as best we can but it is not working how we expect.
The form is located here: http://nscss.org/civicrm/contribute/transact?reset=1&id=3

The error:
1. Select any membership level and select "no thanks" from the contribution section. Enter your email only (no other fields are required) and click Continue at the bottom of the page.
2. Notice on the next page no transaction is listed and no Google button (we are using Google checkout) appears
3. If backup (click the browser back button) and you make a small contribution, even $1 in the "other" field then both the membership fee and the additional, optional contribution will show up and the Google continue button will showup and will process.

How we have it configured
Yes: Contribution Amounts section enabled
Yes: Require Membership Signup
Yes: Separate Membership Payment

Is there something we are missing? We are currently running version 2.1.1, and this bug is still an issue in 2.1.2 according to Lobo. We are running on Drupal 6.6

Thanks!

Thanks so much!