Kicad Symbols description not all chars allowed

[Dunkelwind]

Kicad Symbols: description can includes special characters:

    (property "ki_description" "Diode, anode on pin 1, for simulation only!" (id 7) (at 0 0 0)
      (effects (font (size 1.27 1.27)) hide)
    )

--> STRING: ("_"|LETTER|DIGIT|"#"|"."|"-"|":"|"~"|","|"!"|"="|"+")+