PackageFormat value as 0

I am getting the value for field PackageFormat as 0 in sysssispackages table. My package is SSIS 2008 and is deployed to SQL Server 2008 server using "Save Copy As" option from BIDS 2008. What does 0 signifies? Can this have a bit of mention in the documentation? Opened a thread on SSIS MSDN forum also: http://social.msdn.microsoft.com/Forums/en-US/sqlintegrationservices/thread/0e8ff938-6fff-46fb-a979-7355ea2d3545