A number of iPhone users are voicing their displeasure over a bug in iPhone software 3.1.2 that sees the phone randomly start searching for service. According to a thread on the Apple Support Discussions site, the problem appears to be software related, as users on AT&T, Rogers Wireless, and Telus have been affected; the only current fix once the phone begins searching is to reboot the device. It is unclear as to whether the problem is limited…