JPMorgan Chase CEO Jamie Dimon is taking the rare step of meeting with the heads of the biggest buyout shops to assure them that he’s behind his new — but relatively unknown — head of the team that serves private-equity firms.

According to sources familiar with the matter, Dimon has recently accompanied Larry Alletto, who now runs JPMorgan’s financial-sponsors group, to meetings with buyout barons amid industry chatter that Alletto has had trouble getting phone calls to private-equity firms returned.

While Alletto, who spent years serving buyout firms and arranging leveraged loans at Bear Stearns, is well regarded as a lender, he doesn’t yet have the deep relationships often found with someone in his new role — thus the sit-downs involving Dimon.

A JPMorgan spokeswomandismissed the talk about Alletto as an unknown: “This sounds like sour grapes,” she said.