Why Authorization header gets removed in iOS PATCH requests?

there. I got a very strange problem. The thing is that when i'm trying to send PATCH requests server says that no Authorization header contains token. The same for PUT request.Tried to sniff and found out that no Authorization header is sent at all. While any other types of request contain Authorization header. First thought its Alamofire framework specific problem, but using NSURLConnection requests and NSURLSession tasks gave me the same: NO AUTHORIZATION HEADER IS SENT!

Here is my code used for Alamofire:

Alamofire.request(.PATCH, path, parameters: ["email":"new@mail.com"],     encoding: .JSON, headers: ["Authorization":"token \    ((User.sharedUser().token)!)"]).validate().responseJSON { (response) in
            if response.response?.statusCode == 200{
                print("success")
            }else{
                print("Error")
            }
        }

and here is code with NSURLConnection:

let request:NSMutableURLRequest = NSMutableURLRequest(URL:url)
request.HTTPMethod = "PATCH"
request.addValue("\(token)", forHTTPHeaderField: "authorization")
request.addValue("application/json", forHTTPHeaderField: "Content-Type")

do{
    let bodyData = try NSJSONSerialization.dataWithJSONObject(["email":"nuv@gmail.com"], options: [])
    request.HTTPBody = bodyData
    NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue.mainQueue())
    {
        (response, data, error) in
        if let mdata = data {
            let contents = NSString(data:data, encoding:NSUTF8StringEncoding)
            print(contents)
        } else {
            print(error?.localizedDescription)
        }
        }
}catch{
    print("failed serialization")
}

IIRC, the Authorization header is one of those headers that NSURLSession reserves for its own purposes, and may overwrite with its own values—particularly if you're sending something that looks like normal HTTP authentication.

Can you send an X-Authorization header instead?