DataFrame Property On MapControl/OverviewMapControl Not Being Set

I started working with the OverviewMapControl property yesterday. I cant say that I have actively worked with this control before as part of the ArcGIS Server web controls. I thought it should be pretty easy to get it going although I started to run into a few problems very quickly.

The MXD contains elements for the PageLayout which gets used by other parts of the application. Since a requirement was that the PageLayout contains a overview map, the guys created a new data frame and added a layer for this index map.

Coming back to the application, the ArcGIS Server is setup to use the active dataframe, and there is no data frame specified on the MapControl. As expected it displays the right dataframe. Ok, now we add the OverviewMapControl and buddy this with the MapControl. Defaulty this displays the same data frame as that of the MapControl. We need it to display the overview map data frame.

So specifying the data frame in the DataFrame property?. One would think this would work and override the one specified on the ArcGIS Server?, but it doesnt. I have been trying heaps of different combinations and other tricks but havent been able to get this to go. I thought it could of been the OverviewMapControl so I decided to test this in a new application with just a MapControl, and the exact same thing happens.

If the ArcGIS Server is set to the active data frame, specifying anything in the DataFrame property of the MapControl or the OverviewMapControl has no effect.
If the ArcGIS Server is set to a specific data frame, specifying anything in the DataFrame property of the MapControl or the OverviewMapControl has no effect.

Even if you type garbage into the DataFrame property it has no effect?, this makes me think if this property actually works?, or is this a bug?
Im going to clarify with ESRI.

I was able to work around this by creating another MXD and then buddying the controls together. This a messy though, I would really like to have everything maintained in the one MXD.