The report filed before the Margao district and sessions court Wednesday by prison authorities also said a SIM card seized from Tejpal's prison cell at the Sada sub-jail, 35 km from here, was registered in the name of a woman from a Panaji suburb.
It said Tejpal regularly called Sheela Lunkad, who is Tejpal's partner in a hospitality venture.
Sheela Lunkad, Rajeev Lunkad, Tejpal and his wife Geetan Batra Tejpal are partners in a private limited company.
The report added that Tejpal also called a woman called Manjiri, based in Delhi's Saket area, at regular intervals, besides several other phone numbers in the national capital.
"We are in the process of writing to the mobile service providers for proper contact details of the owners of these numbers. They will be included in the probe as to how the mobile phone was sneaked into prison," said an official associated with the inquiry.
The probe also revealed that the SIM card - bearing phone number 7350533170 - which was recovered from Tejpal's shirt collar was registered under the name of Thereza, residing in Taleigao, a suburb of Panaji.
Tejpal has denied possession of the SIM card, but was booked under various sections of the Indian Penal Code and of the Prison Act.
A junior woman colleague has accused Tejpal of rape during a conference organised by the Tehelka founder in Goa. The woman said she was sexually assaulted twice in November.
After an investigation, the Goa crime branch charged Tejpal with sexual harassment, wrongful restrain, rape, taking advantage of his official position, and committing rape in his custody.