BBSAK 3rd party application recognition

[abhijeetkusre]

hello,
i am interested to know how BBSAK Application is differentiating between 3rd party application and default application even if they are starting with net_rim_bb.
for example i installed face book in blackberry 8300 having firmware 4.5
the module is starting with net_rim_bb_facbook.
so how does it recognize as 3rd party application.
it has same vendor and modules as of deafult and core application.
only difference i saw was of version.
default application are having same version as of the Firmware of the device.

Any help would be appreciated..(urgent)

Thanks