Chart axis date intervals

I'm using Excel 2007 and I want to plot data vs dates. Furthermore I want the dates on the dates axis to increment by month not by a certain number of days. So something like this:
1-Jan-09
1-Feb-09
1-Mar-09
...

There's the Major/Minor Units on the Axis Options screen but I cannot type in a constant number since the number of days for each month is different.

Any help would be appreciated.

Thanks. I'm using a box plot and the vertical axis is for the dates. Could you tell me specifically how I should do it?

I hate to be asking this but where do I set the data labels on the box plot? Also how can I have the X values set to 0 when I need to display them on the plot? I'm probably missing something. Let me write down what my dataset looks like:

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The series for the chart (Y axis) look like this:

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and the X axis series are COL E.

Based on this info could you please reiterate your response? I appreciate all your help! Btw again, I'm using Excel 2007.

Sure. This is the dataset:

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And the data series for the X and Y axes of the plot are defined as follows (this chart has 5 series for the Y axis -to get here right click on the plot and select "Select Data...". Then add 5 series with the following values):

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The X axis labels for all above series is defined as:

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The resulting plot is attached. Thanks helping out!!

Here is the spreadsheet.

Thanks! That looks just like what I want. It's a shame Excel doesn't have a built-in support for something like that already.

Btw how did you add the dummy series? When I click on Add to add a new series I only get to choose data for the Y axis whereas the way you have it it's got both the X and Y axes in one series.

Thanks guys. Issue is resolved