Birla Sun Life Flood of Spam Calls

Birla Sun Life just demonstrated a gang-spam when they called me from multiple phone numbers multiple times. 

Here are the details: 


Calls from Birla sun life: 
Date: 23-April-2013

Details: (Number; Time)
9324331121; 17:27:23
9324331121; 17:27:36
02232260259; 17:27:45
02232260259; 17:28:40
02232260258; 17:28:47
02232260258; 17:29:35
02232260258; 17:31:38

I have reported all of them to the DND service (1909).