Here is the basic code:
<telerik:RadTextBox ID="RadTextBox1" runat="server" TextMode="MultiLine" Enabled="False"> </telerik:RadTextBox>

If Czech keyboard layout is used it is not possible to enter any numeric value in the control.

Repoduction steps
Alternative 1
1) Browse to http://demos.telerik.com/aspnet-ajax/input/examples/overview/defaultcs.aspx
2) Click on Phone field -> whole field gets selected
3) Enter 'a' -> One time red flashing border and caret moves 1 position
4) Press 'a' again -> One time red flashing border and caret does not move

Alternative 2
1) Browse to http://demos.telerik.com/aspnet-ajax/input/examples/radmaskedtextbox/firstlook/defaultcs.aspx
2) Click on IP address field -> whole field gets selected
3) Enter 'a' -> Caret moves 1 position, no one time flash of border
4) Press 'a' again -> One time red flashing border and caret does not move

Expected behaviour at step 3 in both cases:
One time red flashing border and caret should be at first position

The RadTextBox (and other input controls as appropriate) should have an aspx property to automatically trim leading & trailing whitespace from user input. This will help ensure that good quality data is passed to the database.

The only way this can currently be done is to custom code "mytextbox.Text.Trim();" for every control on the page, before the property is sent to the database.

RadInputManager add property InputType

Fixed: RadMaskedTextBox value not submitted correctly when DisplayMask differs from Mask in some cases.