Just one month after Universal Pictures sued Mike Myers for allegedly breaching his contract to write, produce and star in “Dieter,” based on one of his “Saturday Night Live” characters, the co-producers of the planned film have also slapped a $30 million suit on Myers. Imagine Entertainment, which is headed by Ron Howard and Brian Grazer, filed suit on Thursday and issued some stinging comments about Myers to Variety. “He claimed he had not approved the screenplay,” said Imagine. “Who wrote the screenplay? Myers.” The statement then went on to say that Myers repeatedly causes “serious damages to those with whom he deals through selfish, egomaniacal and irresponsible conduct.” Myers’s attorney called Imagine’s claims “fictional and without merit.” He also said that his client — who didn’t receive a single penny for his work on “Dieter,” the lawyer claims — has refrained from countersuing anyone “because of discussions that have been taking place between Universal and Mike Myers’ representatives.”