You don't need to purchases new License
Symantec Protection Suite Enterprise Edition 4.0 includes:
o Symantec™ Endpoint Protection 12.1
o Symantec™ Mail Security for Microsoft Exchange 6.5
o Symantec™ Mail Security for Domino 8.0
o Symantec™ Messaging Gateway 9.5
o Symantec™ Web Gateway 5.0
o Symantec™ System Recovery 2011 (Desktop Edition only)
o Symantec™ Network Access Control 12.1 (Self – Enforcement)
o Symantec™ Workflow 7.1
o IT Analytics 7.1
https://www-secure.symantec.com/connect/blogs/symantec-protection-suite-enterprise-edition-40
Symantec™ Protection Suite Enterprise Edition 4.0 Data Sheet