Apple CEO Steve Jobs is quietly preparing to launch iPhones sporting faster 3G Internet capability and lower-end versions, according to an analyst.

“Our latest channel checks point to a significant production build of a 3G iPhone beginning in the month of June,” Bank of America analyst Scott Craig wrote Friday in a note to clients. The analyst also said that lower-end iPhones were in the works.

That means new iPhones could hit the stage at Apple’s Worldwide Developer Conference, scheduled for June 9-13 in San Francisco. The Bank of America report said that the 3G version would likely come out in Apple’s second quarter.

Internet is the Achilles heel of Apple’s iPhone. The phone’s 2.5G Edge connection has been widely criticized from the start. The release of the phone with the slower connection likely left many buyers on the sidelines. It also means that coming 3G versions could steal away business from rival 3G phone makers.

Bank of America, which has a $160 price target on Apple, makes a business in the securities of the Mac maker.

Apple shares gained $2.76, or 2 percent, at $143.01 in trading.