Problem using NSURLConnection and server trust authentication challenge - iphone

Question

Good day to everybody,
I'm working on a singleton that should manage the download of contents through the internet, I know that exist ASIHttp request and that is an excellent lib, but I have my own reasons for not using it.
The class works pretty fine except for one thing: I'm trying to deal with the public folder of my MobileMe account without success. I uploaded a file inside it and trying to download using my class.
Reading some questions on stackOF and reading docs I came up into that code, but it seems to do not work:
- (BOOL)connection:(NSURLConnection *)connection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace
{
if([protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
{
NSLog(#"SERVER TRUST AUTH");
return YES;
}
else if([protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic])
{
NSLog(#"HTTP BASIC AUTH");
return YES;
}
NSLog(#"NO AUTH");
return NO;
}
- (void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge
{
NSLog(#"Authetication");
if ([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust])
{
NSLog(#"Trust Challange");
SecTrustResultType trustResultType;
OSStatus err=SecTrustEvaluate(challenge.protectionSpace.serverTrust, &trustResultType);
NSLog(#"SecTrustResult %lu %ld",trustResultType,err);
if (trustResultType == kSecTrustResultProceed || trustResultType == kSecTrustResultConfirm || trustResultType == kSecTrustResultUnspecified) {
[challenge.sender useCredential:[NSURLCredential credentialForTrust:challenge.protectionSpace.serverTrust] forAuthenticationChallenge:challenge];
}
else{
[challenge.sender cancelAuthenticationChallenge:challenge];
}
// [challenge.sender continueWithoutCredentialForAuthenticationChallenge:challenge];
}
else if([challenge.protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodHTTPBasic])
{
NSLog(#"HTTP Challenge");
NSURLCredential *credential = [[NSURLCredential alloc] initWithUser:#"user" password:#"pass" persistence:NSURLCredentialPersistenceForSession];
[[challenge sender] useCredential:credential forAuthenticationChallenge:challenge];
[credential release];
}
else{
[[challenge sender]cancelAuthenticationChallenge:challenge];
}
}
Now I'm stuck because from the log I can see that the evaluate function return a result of 4 that corresponds to a kSecTrustResultUnspecified but nothing is working even if I say to the challenge sender to continueWithoutCredentialForAuthenticationChallenge.
The url of the file is : https://public.me.com/XXXX/Objective.zip (link removed)the zip is the ObjectiveZip library that I also implemented in my class.
Any suggestion?