Messages corrupted?

Is it possible for a message to get corrupted? I see that the 802.15.4 MAC frame have a CRC field, so probably almost all packets with errors will be silently discarded.

This also means it is not possible to implement any kind of forward error correction at a message level?

Edit 1:

I mean, let’s imagine a message is 100 bits long, if only 5 bits are corrupted all messages will be discarded at the MAC level because of a wrong CRC.
If it was possible to accept the messages even corrupted, a FEC could possibly recover it and so have better throughput on a high noise channel.

A particular message will not likely be corrupted, however you have no promise than ANY message makes it to the final destination.

Since you can send binary data, you could of course encode it in any form you desire, adding any ECC you want. This would not cover the Xbee network overhead, but it would cover yoru data.

Is any way to deactivate CRC??. I want to see a message with wrong bits.