Linkedin API Error Invalid Signature in iPhone Starter Kit

I've tried to run the OAuthStarterKit xcode project out of the box, entered the correct api key/secret and oauth user token/secret. When I get to authorizing with this code:

    OAMutableURLRequest *request = 
        [[[OAMutableURLRequest alloc] initWithURL:requestTokenURL
                                         consumer: self.consumer
                                            token: self.requestToken   
                                         callback:linkedInCallbackURL
                                signatureProvider:sha] autorelease];

It returns the error "signature_invalid", which seems to indicate an incorrect signature. the clear text and secret have a mix of upper and lower case chars, I'm not sure that that should make a difference.

If I use

requestTokenURLString = @"https://api.linkedin.com/uas/oauth/requestToken?scope=r_basicprofile+r_emailaddress";

It returns invalid sig... but if I use a basic permissions call

requestTokenURLString = @"https://api.linkedin.com/uas/oauth/requestToken;

It works fine, but it means I only have basic profile permissions, where I need things like the email address.

Entering all of the same data in the test console seems to work fine here:

https://developer.linkedin.com/oauth-test-console

Anyone know what I should be doing, thinking, or where I should be looking? Further log info:

oauth_problem=signature_invalid
oauth_problem_advice=com.linkedin.security.auth.pub.LoginDeniedInvalidAuthTokenException while obtaining request token for: POST https://api.linkedin.com/uas/oauth/requestToken/oauth_callback:hdlinked://linkedin/oauth 
oauth_consumer_key: XXX
oauth_nonce
oauth_signature_method: 3DHMACSHA1

2012-09-04 23:36:07.054 OAuthStarterKit[31952:c07] secret: TIDi9XXXXXXX
2012-09-04 23:36:07.054 OAuthStarterKit[31952:c07] base64EncodedResult: JXW6ZWUpXv7ba98o2hcUXodDhmg=

I'm using the code sample from here https://github.com/synedra/LinkedIn-OAuth-Sample-Client

Edit: Will be trying to get to the bottom of this tomorrow and answer my own question if no one beats me to it.

After much wrangling with the Linkedin API Beast, I found the issue to be in the way things are encoded, a long story, in OAuthLoginView.m in method 'requestTokenFromProvider' I needed to include the param 'scope' with the relevant permissions in a OARequestParameter object.

(based off the github repo -> https://github.com/synedra/LinkedIn-OAuth-Sample-Client)

After that, wherever you're making your api call, (in OAuthStarterKit for example) like in ProfileTabView::profileApiCall you can fire off URL posts like this: http://api.linkedin.com/v1/people/~:(id,first-name,last-name,industry)"]; or if you need their email address, it appears (as long as you've got permission to access email, you can grab that too as simply as this:

NSURL *url = [NSURL URLWithString:@"http://api.linkedin.com/v1/people/~:(id,first-name,last-name,industry,email-address)"];

See the code for using a OARequestParameter in the URL request below...

- (void)requestTokenFromProvider
{
    OAMutableURLRequest *request = 
            [[[OAMutableURLRequest alloc] initWithURL:requestTokenURL
                                             consumer:self.consumer
                                                token:nil   
                                             callback:linkedInCallbackURL
                                    signatureProvider:nil] autorelease];

    [request setHTTPMethod:@"POST"];

    OARequestParameter * scopeParameter=[OARequestParameter requestParameter:@"scope" value:@"r_fullprofile r_contactinfo r_emailaddress"];

    [request setParameters:[NSArray arrayWithObject:scopeParameter]];

    OADataFetcher *fetcher = [[[OADataFetcher alloc] init] autorelease];
    [fetcher fetchDataWithRequest:request
                         delegate:self
                didFinishSelector:@selector(requestTokenResult:didFinish:)
                  didFailSelector:@selector(requestTokenResult:didFail:)];    
}

And for a more in depth short cut to using linkedin's API I'll keep some quicktips on my blog here ->http://techrantnz.blogspot.com.au/2012/09/the-linkedin-api-with-oauthstarterkit.html

If you wish to check things are working, check the method which is called if it succeeds

- (void)profileApiCallResult:(OAServiceTicket *)ticket didFinish:(NSData *)data

If you output the response body you might see something like:

2012-09-05 21:40:55.109 OAuthStarterKit[12244:c07] profile: {
    emailAddress = "[my email]@gmail.com";
    firstName = Dave;
    id = XXXXXX;
    industry = "Information Technology and Services";
    lastName = "XXXXXXXX";
}