MobilePhone (Nokia) is described here...

[[http://www.3gpp.org/ftp/tsg_sa/WG3_Security/TSGS3_31_Munich/Docs/PDF/S3-030730.pdf]]

For iPhones the Blogentry at [[http://blog.kurtzconsultingservices.com/search?q=iphone+cacert]] can be usefull.