Celtic have shown their interest in England international David James and are keen to sign him according to Lennon. Lennon has Pole Lukasz Zaluska and American Dominic Cervi but wants a major figure to compensate for the loss of Boruc, who has left for Fiorentina.
"We are still a long way off and it's early days in terms of negotiation," said the Celtic manager.
James' former club Portsmouth have withdrawn an offer they made in May.
The 39-year-old goalkeeper made 138 appearances for Pompey and, according to club administrator Andrew Andronikou, wanted to be their player-manager.