Locale with URL aliases that contain accented characters

I'm having an issue on a Spanish website. Whenever t() is called on a page that contains an accented character, it throws an error similar to this:

URL: /printmail/dailyword/protecci�n-tuesday-april-16-2013
General error: 1366 Incorrect string value: '\xF3n-tue...' for column 'location' at row 1

That URL is coming from request_uri() and causing an error when trying to insert the t() text into the locales_source table.

Full error:

    [errorInfo] => Array
        (
            [0] => HY000
            [1] => 1366
            [2] => Incorrect string value: '\xF3n-tue...' for column 'location' at row 1
        )

    [query_string] => INSERT INTO {locales_source} (location, version, source, context, textgroup) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4)
    [args] => Array
        (
            [:db_insert_placeholder_0] => /printmail/dailyword/protecci�n-tuesday-april-16-2013
            [:db_insert_placeholder_1] => 7.14
            [:db_insert_placeholder_2] => Protección - Tuesday, April 16, 2013
            [:db_insert_placeholder_3] => 
            [:db_insert_placeholder_4] => default
        )

Maybe I'm missing something? For now, I've removed the t() call that is mainly having this issue (and the titles are already translated to Spanish)