Specifying a default for checkboxes does not respect the Required field . . .

When creating or modifying a node type and adding one or more check boxes, if they are set to 'Required' and a 'Default value' is selected, when creating a node of that type and unchecking all check boxes, the node can be saved. If the node type does not have any 'Default value' selected, the 'Required' part works as expected.

To verify this, I went through the following process:
* I created a brand new installation of Drupal 5.2.
* I installed the Contact, Text & Option Widgets modules and disabled all other unnecessary modules.
* I edited the Story node type, and added a single field with the 'Required' and 'Multiple values' check boxes checked and added one or more values to the 'Allowed values list' text area.
* I then saved, re-configured the node type, selected one of the options as a 'Default value' and saved it again.
* Next, I created a story content type, filled in the title and unchecked all check boxes for the added field.
* I was then able to save the node w/o any problem.

To contrast that, go back and edit the node type and remove all checks for every 'Default values' item and trying saving the content w/o any check boxes checked.

Note: This may be a bug in the Forms API, but since I discovered it in CCK, I thought I'd start here.