Javascript exception is happening when we are using 3 dependant picklists (One Main picklist, One Picklist dependant on the Main Pick List and One more dependant on the Second Pick List) in a Visual Force Page with standard controller extension. This issue is happening only in Chrome browser. The Issue we are getting is "picklist4.js:21 Uncaught TypeError: Cannot read property 'length' of undefined
    at HTMLSelectElement.picklist.onControllerChange (picklist4.js:21)". Because of this error, the dependant picklists are not getting enabled on selection of items in the Main Pick List.