Int32EditBox can't count to 10 ?

When I set the Maximum property of the Int32EditBox to 10, it can only count up to 9.
Setting max to 12 works, setting max to 7 works, but setting max to 10 doesn't!

I installed the evaluation version of WPF studio. I use that with Visual Studio 2010 and .NET 4.0

Here is what I did to verify:
.

Create a new WPF application

Drag the Int32EditBox from the toolbox onto the MainWindow

Set Maximum to 10

Run the program

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It is now IMPOSSIBLE to enter 10 into the edit box.
.

Set Maximum to 11

Run the program

.
Entering 10 or 11 now is no problem.
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When the max is set to anything but 10, the Int32EditBox works fine. Set max to 10, and entering 10 becomes impossible.

Thank you for your time.