Before we discuss birthplace of Sariputra, we first try to correlate the places from various sources in history and establish possible relation among them.
Nalanda ( of Pavarika, Pali ref) = Nala (Fahien) =Nala, Nalika, Nalaka ( Birthplace of Sariputra, Pali Sources)= Kalpinaka( birth place of Sariputra, Xuanzang)= Nalanda(jain Literature)= Nalanda ( Arthasastra) = Nalanda ( Monastery and birth place of Sariputra, Taranatha and other Mahayana texts)
A) Nala (Fahien), Nala, Nalika, Nalaka (Birthplace of Sariputra, Pali Sources) = Kalpinaka (birth place of Sariputra, Xuanzang)
Since all accounts mention it as the birth place of Sariputra, let us assume that they are talking about same place and also that these places don’t have any reference to Nalanda Mahavihara. So, Nala, Nalika, Nalaka, Kalpinaka are all names of one single place.
B) Nalanda ( of Pavarika, Pali ref) = Nalanda (jain Literature)
In the Pali literature there are evidences where it is mentioned that Nalanda is a centre of activities of Nirgranthas (jains). They are referring to Nalanda of Pavarika mango grove and that would be same as Nalanda where important disciples (Lepa & bhadrabahu) of Mahavira lived and Mahavira himself preached.
C) Nalanda ( Arthasastra) – in Arthasastra, its mentioned that Nalanda is a suburb of Rajgriha
Nalanda of Arthasastra may be or may not be same as mentioned in Pali sources because this was written some 200 years after the Buddha and Mahavira time.
So we have to find a relation between three
Sariputra birthplace (Nala, Nalaka, Nalika & Kalpinaka) = Nalanda of Pali Literature = Nalanda of lama Taranatha in relation with Nalanda Mahavihara