Bug 118644 Hint for Date Time Parameters
The hint you give for date time parameters (Please enter date ... pattern: MM/DD/YYYY ....) is only true if the date is unformatted. If you apply a format, you must enter it according to it. So it's quite confusing!
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/dialogs/ParameterDialog.java
else if ( DesignChoiceConstants.PARAM_TYPE_DATETIME.equals( getSelectedDataType( ) ) )
			{
				DataTypeUtil.toDate( value, Locale.US );
			}
			else if ( DesignChoiceConstants.PARAM_TYPE_FLOAT.equals( getSelectedDataType( ) ) )
			{
				DataTypeUtil.toDouble( value );
			}
		}
		catch ( BirtException e )
		{
			return ERROR_MSG_MISMATCH_DATA_TYPE;
		}
		return null;
	}
	private IChoiceSet getFormatChoiceSet( String type )
	{
		IChoiceSet choiceSet = null;
		if ( DesignChoiceConstants.PARAM_TYPE_STRING.equals( type ) )
		{
			choiceSet = DesignEngine.getMetaDataDictionary( )
					.getChoiceSet( DesignChoiceConstants.CHOICE_STRING_FORMAT_TYPE );
		}
		else if ( DesignChoiceConstants.PARAM_TYPE_DATETIME.equals( type ) )
		{
			choiceSet = DesignEngine.getMetaDataDictionary( )
					.getChoiceSet( DesignChoiceConstants.CHOICE_DATETIME_FORMAT_TYPE );
		}
		else if ( DesignChoiceConstants.PARAM_TYPE_DECIMAL.equals( type )
				|| DesignChoiceConstants.PARAM_TYPE_FLOAT.equals( type ) )