I have been trying to get email encryption to work on my iPad using a S/MIME key which I created in Keychain Access on an iMac. I failed. I posted a summary of my experience on MacOSX Hints. To read my experience click here.
BTW, I did the same testings with S/MIME certificates from Comodo in iOS7. The result for all these testings were the same as the ones using the Keychain Access generated certificates.
BTW, I did the same testings with S/MIME certificates from Comodo in iOS7. The result for all these testings were the same as the ones using the Keychain Access generated certificates.