text-field-pane

Hello everyone. I am trying to use the keys of the keypad to enter numbers in a text-input-pane; I have traced the problem to the function x-event-to-key-name-and-modifiers located in Backends/CLX/keysyms.lisp; what I see is that the function returns the first value (the keyname) as nil. Does anyone else have problems using the keypad?