Mac Os 10.4 France Decimal Point


On Mac OS 10.4 system
When using France setting (to get an AZERTY keyboard) and France numeric setting, to use decimal point and not decimal comma , this setting is not recognized by MS Excel, who present its files with decimal comma. Decimal point is mandatory for us, to interface with other softwares.
This problem did not exist in Mac OS 10.3

The problem stays the same if we use an English installation for MacOS (but we need to keep the azerty keyboard)