Why when I upload a picture with its name with international characters, like: ábc.jpg to WordPress, the File name appears as: bc.jpg?

Instead, its Title and URL are correct. Please, see this screen capture: http://d.pr/i/1oFG

Is this a bug?

P/S: Please, PAY ATENTION that this behavior only occurs with images that the international character is the FIRST letter of its name, and NOT when are in the middel of the name.