steps to reproduce

1. load the zul below in French locale

   <datebox format="MMM yyyy"  lenient="false"/>
   

2. enter mars 2015 or select at calendar

actual result

format error message displays

expected result

no format error message displays

root cause

The March in French , “mars”, starts with “mar”, and “mar” is also Tuesday in French (localizedSymbols.S2DOW in zk.fmt.Date.parseDate).