Nexus 4 not switching back to HSPA+ after being in wifi

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http://forums.androidcentral.com – Hi Guys, Im a new Nexus 4 user. I switched from the iPhone camp. In the case of an iPhone, whenever Id move out of a wifi area, the data plan would kick in immediately. However, this is not happening in the case of the nexus 4, ie. I dont have connectivity. Im currently on an AT&T connection. Any help would be appreciated. Thanks (HowTos)