Google client-login in Objective-C

I am trying to write a code for google client-login in objective-c. I get Auth with email and password from "https://www.google.com/accounts/ClientLogin" and I can successfully login google by POSTER (firefox).

When I write the code for objective-c, however I cannot login and get error code 401.

Could someone help me what I am doing wrong? Here is my code.

// URL to check user info
NSURL *url = [NSURL URLWithString:@"http://www.google.com/reader/api/0/user-info"];

// authorization 
NSString *auth = authString;

// create request
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url];

// add auth information in header
auth = [NSString stringWithFormat:@"GoogleLogin auth=%@", auth];
[request addValue:auth forHTTPHeaderField:@"Authorization"];

// send request
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
if (connection) {
    NSLog(@"request send.");
} else {
    NSLog(@"Connection Failed when getting feeds.");
}

Answers

I have managed to log-in with Objective-C. I found my Header "Authentication" was null even though I set it in the code. I needed to remove %0A (in ASCII) to set the cookie.

Here is the modification I made. (Hope it would be helpful for someone)

// Encode ASCII
NSString * authEncoded = [auth stringByAddingPercentEscapesUsingEncoding:NSASCIIStringEncoding];

// Remove %0A
authEncoded =  [authEncoded stringByReplacingOccurrencesOfString:@"%0A" withString:@""];

// Create value for header
authEncoded = [[NSString alloc]initWithFormat:@"GoogleLogin auth=%@", authEncoded];

I used "authEncode" to set a header and everything works fine so far.

[request addValue:auth forHTTPHeaderField:@"Authorization"];

Need Your Help