I'm clearly misunderstanding the doc, I have a MaskedTextBox to which I'm trying to assign a value, but all I get is nothing in it and it displays the mask character.
Here's the definition of the text box, pretty simple:
<telerik:RadMaskedTextBoxrunat="server"ID="txtUserName"ZeroPadNumericRanges="true"Mask="__________"></telerik:RadMaskedTextBox 
