PS2 Keyboard problem

I have been trying to use the PS2 keyboard library in conjunction with LCD4bit in an effort to display typed characters on the LCD. I have been mostly successful, being able to properly display all letters and numbers, including the keypad numbers, but cannot get the Spacebar, "." or "," keys to display. I echo the characters to the serial monitor, and have properly coded the hex values for these codes. I appears that the keyboard simply isn't sending the hex character shown in the scancode listings. I have tried other keyboards with the same result. Has anyone had a similar problem???