Localization and backward compatibility issues

Hi there;

I am a programmer from Turkey using Rails fondly.
Primarily, I think Rails to create a community for the Turkey.so I
would like to hear your opinion on this subject.

Now I want to talk about problems.

----- Last try to create the project on the rails "C: \Users\Mira߀"
folder found in the direction I received an error.

      Turkish characters in the name of the original name of the
folder, but it is broken out Miraç. and the project can not be
created.

Which used of Rails 3 is the default character set ?
3 version to use the following code required?

@headers["Content-Type"] = "text/html; charset=iso8859-9"

I'm sorry, so my English is not perfect
Thanks for reading.