Well, it ain't so much a bug, as you were supposed to be able to get at least two GECK. The one from Enclave is supposed to give those players who missed the other GECKs possibility to beat the game. Not sure if it was supposed to be able to get three of those, but I usually end up at having two.
Oh, and please, next time put a spoiler tag to the thread name, as your post contained some minor spoilers about the GECK...
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"As we all know, holy men has born during Christmas...
Like mr. Holopainen over there!"
- Marco Hietala, the bass player of Nightwish