Jack -

Yes, this is a well-known and popular duet. Beautiful lyrics and composition.

Today I am thinking of "Maelum Keezhum Moochchu Vaangalaachchu..." I think the film is Priyamudan Prabhu? Also, "Mudhal Murai Thoduvadhu Sugam" from Dhooram Adhigamillai is a "hot" duet that did not get any airtime!