服务器接收的日期多了一个空格

代码：

NSString *jsonD = [NSString stringWithFormat:@"rawJson=%@",[fbUserInfo jsonUTF8String]];
NSData *myRequestData = [jsonD dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];

NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
                                                           cachePolicy:policy timeoutInterval:20.0];

[ request setHTTPMethod: @"POST" ];
[request setValue:[NSString stringWithFormat:@"%d", [myRequestData length]] forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[ request setHTTPBody: myRequestData ];

在代码中的日期2013-06-29T18:33:17+0000。而服务器接收的日期是：2013-06-29T18:33:17 0000，中间多了一个空格。