The DateFormatTransformer assumes the default locale for date transformations.
If your computer or server has its language set to 'es' and the input file has "November 30, 2009", it'll throw an exception.
Here's a reproducible test case:
Define an XML file:
<awardlist><award><expirationdate>November 30, 2009</expirationdate></award></awardlist>
Define the data-config.xml with:
<field column="expirationdate_dt" xpath="/awardslist/award/expirationdate" dateTimeFormat="MMMMM dd, yyyy" />
Exception in thread "main" java.text.ParseException: Unparseable date: "November 30, 2009"