An old bug has new life - Add New Page Error

This bug: www.sitefinity.com/.../add-new-page-error that was fixed in 2011 is back in the wild.

The error message is:
There was an error deserializing the object of type Telerik.Sitefinity.Modules.Pages.Web.Services.Model.WcfPageContext. The value '' cannot be parsed as the type 'float'.

The fix is to include a value in the "Priority in sitemap" field, but there should be validation there to prevent form submission.