SUP 2.1.2 - Login Failed with native iOS application

Hi

We are running SUP 2.1.2 and testing both the SUP101 Tutorial application and our own native iOS application using some of the code from SUP101.  We can get the device to register in SUP however when we get to the point where it evaluates the pin and password of the SUP user (when it runs for the first time) we get Login Failed.  There are no errors in the SUP logs and we have the log level set at DEBUG.  We are providing the normal supAdmin password which we can logon to SCC with.

I have reregistered the users, redeployed the project, regenerated the code - however it still gives the Login Failed error.  Completely stumped with this - does anyone have any suggestions or run into this problem?

Thanks
Leigh