[pestaa]

It's typo, should read as some-bucket.

[j2d3]

I checked and it's corrected in the most current version:

https://github.com/s3tools/s3cmd/blob/master/s3cmd#L2048

The version I have with the typo is 1.5.0-alpha1

[j2d3]

ok, that makes sense! S and C are fairly close together on the keyboard.

Pretty funny typo ;)