modify keyboard layout

[mobidyc]

Hello,

all I want to do is to redefine the keyboard mapping for the first row.

I tried to modify the /usr/share/X11/xkb/symbols/fr file like this:
// First row
key <TLDE> { [ twosuperior, threesuperior, onesuperior, dead_cedilla ] 
}; // ² ³ ¹ ¸
key <AE01> { [ ampersand, 1, dead_caron, 1 ] }; // & 1 ? ?
key <AE02> { [ eacute, 2, asciitilde, 2 ] }; // é 2 ~ É
key <AE03> { [ quotedbl, 3, numbersign, 3 ] }; // " 3 # ?
key <AE04> { [ apostrophe, 4, braceleft, 4 ] }; // ' 4 { — (tiret cadratin)
key <AE05> { [ parenleft, 5, bracketleft, 5 ] }; // ( 5 [ – (tiret 
demi-cadratin)
key <AE06> { [ minus, 6, bar, 6 ] }; // - 6 | - (tiret insécable)
key <AE07> { [ egrave, 7, grave, 7 ] }; // è 7 ` È
key <AE08> { [ underscore, 8, backslash, 8 ] }; // _ 8 \ ™
key <AE09> { [ ccedilla, 9, asciicircum, 9 ] }; // ç 9 ^ Ç
key <AE10> { [ agrave, 0, at, 0 ] }; // à 0 @ À
key <AE11> { [ parenright, degree, bracketright, notequal ] }; // ) ° ] ?
key <AE12> { [ equal, plus, braceright, plusminus ] }; // = + } ±

but It doesn't work, nothing changes.

Where can I go to find documentation about this?
Google didn't help me enough.

Cheers,
Mobidyc