SQL Server setup media does not support the language

I found this workaround from MS connect website:

Go to Control Panel, Regional Settings and change the "Format" language on the first section; close window, re-enter and change format back to your locale. Launch setup of SQL Server and now it should work.

Check out the other workarounds mentioned in the same site.

Also if you give more info about your environment more people will be able to help you.