pass parameter with space web api mvc4

I am using web api MVC4. In the get method I will pass the string parameter, which will have space. During execution it gives error.

my WebApiConfig is like below

     config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );

    config.Routes.MapHttpRoute(
            name: "FindDetailsByCountry",
            routeTemplate: "api/{controller}/FindDetailsByCountry/{country}",
            defaults: new { country = RouteParameter.Optional },
            constraints: new { country = @"^[a-z]+$" }
        );

Now when I run the application

Case 1
input : .../api/contact/
output :
[{"Name":"Ashok","Age":60,"Country":"India"},{"Name":"Nargis","Age":30,"Country":"India"},{"Name":"Nargis","Age":35,"Country":"Iran"},{"Name":"Steve","Age":50,"Country":"South Africa"}]

Case 2
input : .../api/contact/FindDetailsByCountry/india
output :
[{"Name":"Ashok","Age":60,"Country":"India"},{"Name":"Nargis","Age":30,"Country":"India"}]

Case 3
input : .../api/contact/FindDetailsByCountry/South Africa
output : HTTP Error 404.0 - Not Found The resource you are looking for has been removed, had its name changed, or is temporarily unavailable

For case 3, I am getting error. I have checked using these options

1. ...api/contact/FindDetailsByCountry/South+Africa
2. ..api/contact/FindDetailsByCountry/South%20Africa
3. ../api/contact/FindDetailsByCountry/"South Africa"
4. ../api/contact/FindDetailsByCountry/'South Africa'

Still it is giving the same error.
Actually I will use the output in my android application. In android also I have used URLEncoder.encode("South Africa", "UTF-8"). But no result.

Can any one tell me how to pass the parameter South Africa ?
Thank you so much ps2goat for my previous question. It works now.

Thanks