decimal separator for numbers in gtk+-2.x (help!)

[domi <reymond d labogeo pf>]

Hi all !

I upgrade my application from gtk-1.2.8 to gtk-2.2.4, and I am stopped by a 
stupid problem: the decimal separator is now by default a "," instead of a 
"."  
the consequences are catastrophic : the scanf(), or sscanf() function are not 
able now to read files containing always number with "." as decimal 
separator.

Where can I change this setting ? 

I tried to change the decimal separator in the Center of configuration KDE,
but it has no effects on the scanf() functions !

If someone can help me ..

Dominique Reymond