Does anyone have any experience with setting the system language format programatically in Windows 7, e.g. via the SetLocaleInfo API?

I would like to switch my format from English to German in the middle of a test run to test some issues with comma separated decimals, then switch back. I've tried using SetLocaleInfo to specifically set the decimal separator and grouping symbols, but this is not sufficient because there is some code further down the line that appears to rely on the language name. Setting the entire system locale, which would require a restart, is not acceptable.

I am coding in Delphiscript in TestComplete, but since it just calls wrappers around the Windows API functions I don't think it makes much difference. On the other hand, my SetLocaleInfo calls referencing some of the newer Win7 variables like LOCALE_SENGLISHDISPLAYNAME can't find that variable name, so who knows.