SCRIPT5007: Unable to get property 'toUpperCase' of undefined or null reference

[Pajamaman]

I'm getting this error in IE7 mode (IE10) using version 1.12.0 with ASP.NET MVC 4:

SCRIPT5007: Unable to get property 'toUpperCase' of undefined or null reference
jquery.validate.js, line 933 character 4

[nschonni]

Duplicate of #1067