Undefined index in tao_textarea()

In a recent site we were working on we were encountering the error Undefined index in tao_textarea();. We were using tao as our base theme and we were creating a form under node/%node/path. It seemed as though it only occured when we followed documentation of the Drupal Form API by adding in some needed attributes under #attributes.

We came up with a patch and potential explanation for the problem, you can read more at the reported issue in the tao issue queue.