Set cell format language

[EloHailwidis]

I try to format my cell with an Euro french format, like '1 234 567 890.00 €'. I set the cell numFmt to '# ##0.00 [$€-40C]'. But when I open the sheet I get '1234567 890.00 €'. Change the language to 'French (France)' in the Format->Cell menu seems to do the thing. So, how can I set the language for a cell ?

See the 'Montant' column in this file.
test.xlsx

[EloHailwidis]

In my case, I wouldn't have too big numbers so I set the format to '# ### ### ##0.00'. It's not very clean but it works...