Mapping does not work with some characters in KeyRemap4Macbook

I want to map Option+Dot and Option+Comma to word-by-word movement in KeyRemap4Macbook. Option+Dot works but Option+Comma does not. Also using any other character such as W, V etc. instead of Comma does not work. They simply put the symbols normally mapped in keylayout file.

Here are the mapping items:

<item>
    <name>word movement right</name>
    <identifier>private.wordright</identifier>
    <autogen>
        --KeyToKey--
        KeyCode::COMMA,ModifierFlag::OPTION_L,
        KeyCode::CURSOR_RIGHT,ModifierFlag::OPTION_L
    </autogen>
</item>
<item>
    <name>word movement by option + dot</name>
    <identifier>private.wordmovement</identifier>
    <autogen>
        --KeyToKey--
        KeyCode::DOT,ModifierFlag::OPTION_L,
        KeyCode::CURSOR_LEFT,ModifierFlag::OPTION_L
    </autogen>
</item>