Verizon is following AT&T’s lead and is starting to crack down on iPhone users who have jailbroken their devices and are using unsupported software to gain tethering capabilities without paying Verizon for the feature. Forbes reports that Verizon’s new initiative detects when a user is tethering illegally, and redirects them to a Verizon webpage where they can upgrade their accounts to include the $20 wireless hotspot option. Earlier…