The radio station said that Heinz's decision to pull the ad, after more than 200 complaints to the Advertising Standards Authority, had caused uproar at the station.
Gaydar Radio has posted the ad free of charge on its sister website to ensure it gets continued exposure.
The ad, created by Abbott Mead Vickers BBDO, shows a family going about their morning routine with the twist that the mother making the sandwiches is replaced by a New York deli chef to get across the authentic nature of the product.
The chef reminds the father to give him a kiss before he leaves for work and the pair kiss as if the chef were his wife.
The station said that listeners have been emailing in their protests via the Gaydar chatrooms. One listener said: "I am appalled that a company such as Heinz should bow down to such homophobic behaviour. I am incensed by their attitude and such a small number of complaints by comparison."
Some chatroom users have also posted the phone number of Heinz's director of corporate affairs and are encouraging people to call him to protest.
Simon Le Vans, a Gaydar Radio presenter who is leading the boycott campaign, said: "This is gutless to say the least and extremely homophobic. Some viewers who complained said that they didn't want to have to explain to their children why two men were kissing.
"Aside from the fact that they could have explained the 'joke' within the premise of the commercial to their children they plainly felt it inappropriate that their children might ask about homosexuality in general."
According to its own research, the station claims a weekly audience of 340,000, although it does not subscribe to official audience figures from industry measurement body Rajar.