.NET Globalization settings on IIS7 incorrect

Hi

My DataFormatString="{0:c}" to render amounts for a 'English (South Africa) (en-ZA)' culture incorrectly uses a comma (,) as a decimal symbol instead of a period (.) 

So my amounts look like:

R 290,00

instead of 

R 290.00

I've checked the OS settings and they are correct. I believe this might be an error in IIS7's hardcoded culture settings for this culture. Is there anyway we can fix this?

Thanks,

-C