downloadTaskWithRequest wont download simultaneously - http

Question

Okej guys. Here we go!!!
I have created a download manager in objective-C that uses NSURLSession.
I´ve got the manager to call a php script on my server, that creates an output file of a file located on the server(image in this case).
I need to call a php script so I can do the security checks on the call from objective-C.
Objective-C starts downloading the virtual file of the server and saves it to the temp directory on the iPhone. The only thing that doesn't work is simultaneously downloading of the files. If I start three download tasks with downloadTaskWithRequest, the first download task will hang the second download task until it´s finished.
If I trie the same thing with downloadTaskWithURL, I am going to get all the downloads downloading simultaneously, meaning no waiting.
What I want, is to download all files simultaneously, but with the downloadTaskWithRequest, not downloadTaskWithURL.
Code Init NSULRSession:
url = [NSURL URLWithString:kServerURL];
NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
config.HTTPMaximumConnectionsPerHost = 10;
session = [NSURLSession sessionWithConfiguration:config delegate:self delegateQueue:nil];
Code Request File From Server method:
The variable 'question' contains data for the server(Username, Password and file to download)
//Pack it into a NSData
NSString *dataString = [NSString stringWithFormat:#"message=%#",question];
NSData *data = [dataString dataUsingEncoding:NSUTF8StringEncoding];
//Create a NSMutableURLRequest with method and body data
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url];
request.HTTPMethod = #"POST";
request.HTTPBody = data;
//Prepare for call to server
NSURLSessionTask *post = [session downloadTaskWithRequest:request];
//Start the task
[post resume];
Code File Finished Downloading method:
-(void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didFinishDownloadingToURL:(NSURL *)location{
//Contains file destination name
NSString *file = [[calls objectForKey:downloadTask] objectAtIndex:4];
//Move temp file to new location
NSString *destination = [[[[GlobalClass sharedManager] storagewraper] filemanager] moveFile:location.path name:file];
}
-----------------------------------------------------Thanks in advance----------------------------------------------------