Select text in the RadMaskedTextInput then Ctrl + X cuts the text but Ctrl + V does not paste it.

Steps to reproduce:
1) Type 12345. Select 345.
2) Ctr + X.
3) Ctrl + V won't do anything. (345 is not pasted) the result is - "_______________"). 
Expected result is: "345". This  should replace the whole text with the copied one. SelectionStart is not changed after paste.

Notes:  This bug is only for the scenario Cut + Paste in the MaskedTextInput with Mask. 
Pasting in No-Masked MaskedTextInput (Mask="") should work much like pasting in normal TextBox (in the same scenario the result should be "12345").