Metropolitan Magistrate Shefali Barnala Tandon directed Mr Sirsa to appear before the court on January 20.
The court had on October 31 summoned sacked minister Kapil Mishra as an accused on January 20 on a similar complaint filed by Jain.
Mr Jain had filed two separate criminal complaints against Mr Sirsa and Mr Mishra alleging that they had made defamatory statements against him in the media.
In his pre-summoning evidence, he had deposed that the accused person had also used his official Twitter handle to defame him.
The court had earlier recognized the two complaints filed by Mr Jain in May. If convicted, the offence of defamation entails a maximum punishment of two years.
Mr Jain submitted that on May 7, Mr Mishra, who earlier headed the water department in the city government, had made a statement accusing him of giving a bribe to Chief Minister Arvind Kejriwal on May 5.
He had accused Mr Sirsa of making libellous statements by levelling corruption charges against him.
He had said these statements had caused irreparable damage to his reputation.
Kapil Mishra, an MLA from Karawal Nagar constituency, was suspended from the Aam Aadmi Party after he raised corruption allegations against Mr Kejriwal and Mr Jain.