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
{
				inputParameter.setDefaultValue( "\"" + defaultValue + "\"" );
			}
			else
			{
				inputParameter.setDefaultValue( defaultValue );
			}
			if ( dirtyProperties.containsKey( CHECKBOX_HIDDEN ) )
			{
				inputParameter.setHidden( getProperty( CHECKBOX_HIDDEN ) );
			}
			inputParameter.setHelpText( UIUtil.convertToModelString( helpTextEditor.getText( ),
					false ) );
			if ( PARAM_CONTROL_LIST.equals( getSelectedControlType( ) )
					|| DesignChoiceConstants.PARAM_CONTROL_TEXT_BOX.equals( getSelectedControlType( ) ) )
			{
				if ( dirtyProperties.containsKey( CHECKBOX_ALLOW_BLANK ) )
				{
					inputParameter.setAllowBlank( getProperty( CHECKBOX_ALLOW_BLANK ) );
				}
				if ( dirtyProperties.containsKey( CHECKBOX_ALLOW_NULL ) )
				{
					inputParameter.setAllowNull( getProperty( CHECKBOX_ALLOW_NULL ) );
				}
			}
			else
			{
				inputParameter.setProperty( ScalarParameterHandle.ALLOW_BLANK_PROP,
						null );
				inputParameter.setProperty( ScalarParameterHandle.ALLOW_NULL_PROP,