Got to Settings->Language and input, under the physical keyboard category select sec_keypad
Make sure the "Selected keyboard type" is "Default".
If it is not then: Select keyboard type and make sure none of the options is selected.
At this point everything will work. The only difference in the option is that the shift and function keys will now work like a standard keyboard function, keys must be held down to be in affect (unlike the press the shift then press the letter functionality that it previously had).