1) Your ActionForm should extend ValidatorForm. If you overwrite the validate method, you will need to make sure that it makes a call to the super.validate method.
2) ApplicationResources is not an xml file. It should look like this:
prompt.reportType =Report Type
prompt.productLine =Product Line
3) You are making the display of messages harder than it should be. All
you should need in the jsp is <html:errors/>. If you want the extra formatting, it will handle it for you if you have entries for:
errors.header
errors.footer
errors.prefix AND
errors.suffix