Issue with using dual vertical axis in flex charts?

Question

I am plotting two line series on a single LineChart which share the same horizontal axis, but have different vertical axis on the left and right of the chart:

<mx:LineChart id="linechart1"   width="100%"  height="100%" showDataTips="true" seriesFilters="[]">

            <mx:horizontalAxis>
                <mx:DateTimeAxis displayLocalTime="true"  dataUnits="seconds"  labelUnits="seconds"/>

            </mx:horizontalAxis>
            <mx:verticalAxisRenderers>
                <mx:AxisRenderer placement="left" axis="{Vaxis1}" />
                <mx:AxisRenderer placement="right" axis="{Vaxis2}"/>
            </mx:verticalAxisRenderers>
            <mx:series>
                <mx:LineSeries  xField="DateTime"  yField="Price1">                                                   
                    <mx:verticalAxis>
                        <mx:LinearAxis baseAtZero="false" id="Vaxis1" autoAdjust="false"/>
                    </mx:verticalAxis>                                          
                </mx:LineSeries>                                        
                <mx:LineSeries id="agentlegend"  xField="DateTime" yField="Price2">

                    <mx:verticalAxis>
                        <mx:LinearAxis id="Vaxis2"  baseAtZero="false" autoAdjust="false"/>
                    </mx:verticalAxis>                                          
                </mx:LineSeries>                                        
            </mx:series>
        </mx:LineChart>

In the first Vaxis , the Price1 varies between 20 to 25 .while , in the second Vaxis Price2 varies anywhere between 20 to 25 but occasionally has a zero value . When Price2 drops to zero for once , the whole chart adjusts into 2 straight lines with no granular view of the price changes . I want scaling on left Vaxis independent of the price change in Right Vaxis values .

I know you can do this by setting maximum and minimum for both charts independently . But , i have huge amounts of real time data coming in , setting the charts minimum and maximum dynamically for each update i get and redrawing it will be a bad idea .

Is there anyway to do this without setting the max and min , i thought by default flex provided the feature to scale the two Vaxis independently according to http://livedocs.adobe.com/flex/3/html/help.html?content=charts_types_12.html

Thanks sanre6