Today I discovered why it is that the French have been placing a space in front of colons (:), and it has been driving me mad.
In English it is usually seen as being wrong to place a space before a colon. However according to Lars Aronsson on the lingu-dev mailing list, it is normal practice in French to place a space before the colon.
You learn something new every day.
The correct rule for French typography is to put a thin non-breaking space in front of colons etc.
If (for whatever reason) this is not possible, the rule is to put no space at all there. I tried to explain this to Eric B in the OOo Wiki, but he continiues to pollute the Wiki with his faulty typography.