The transaction fc3f81c625720063c5cab2145bcb5ef20b13ff0aa73b0b2435ffdb645acfcb8b
has the warning "Transaction rejected by our node. Reason: The transaction is not final." on Blockchain.info.
The same transaction shows up with five confirmations on Blockexplorer.com.
What does that "the transaction is not final" mean, and why did blockchain.info reject the transaction?