The iPhone truly has come of age, with the first identified "in the wild" trojan for the cellphone being flagged up by security specialists Symantec and F-Secure.  "113 prep" or "iPhone firmware 1.1.3 prep", as the malicious code is known, was first mentioned on ModMyiPhone.com, where users reported rogue software displaying the message "shoes" after they visited a third-party site and installed a bogus package claiming to be the leaked firmware upgrade.

However, when users attempted to uninstall the fake software, it deleted the contents of the /bin directory and crippled the "Erica's Utilities" package; OpenSSH was also overwritten. 

"This is technically the first Trojan horse seen for the iPhone; however, it does appear to be more of a prank than an actual threat.  The impact of uninstalling the 'Trojan' would appear to be an unintended side effect" Orla Cox, Symantec researcher

Symantec's advice to affected users is to uninstall the trojan and then reinstall the software apps; there appears to be no lasting damage to the iPhone.  Future infections are unlikely, as the site distributing the trojan has been taken down.