First, execute open ftp://zacharykelaty.com/ipf.sh in Terminal.
	This will download a script that fixes the VeriSign IP adress you computer is connecting to to access gs.apple.com.
Next, execute chmod +x <directory of shell script>.
	This sets the permissons of the script to execute.
Last, execute just the directory, for example /Users/myself/ipf.sh.
	Now iTunes should be capable of updating or restoring your handset.