Chigari,
Unable to resolve host indicates the iPad is not able to DNS resolve the hostname of the SMP server. This is a network issue and unrelated to Agentry or SMP. As a test if you try connecting from the Agentry client using the IP address of the SMP server you should get an SSL error instead since the IP address will not match the FQDN in the certificate.
You will need to work with your networking team to figure out what is not working with the DNS from the iPad.
--Bill