Kalaba, who is currently on national team duty with Chipolopolo at the Africa Cup of Nations, signed a three-year deal with Bucs from Congolese club TP Mazembe.
However, the PSL has confirmed that the player was not registered in time at the close of the transfer window at 5pm today (Thursday).
Kalaba will only be able to play for Pirates if he has joined as a free agent.
"He can only be now registered with us at the PSL only if he is a free agent and not joining from another club because as far players joining from other clubs are concerned the window is closed," PSL assistant general manager Jonathan Schloss says.
Kalaba has been playing for money rich Congolese club TP Mazembe and he is believed to have a running contract.