This isn't that uncommon, unfortunately I've run across similar customs scams. WE had a computer spend six months in customs in ecuador -- same deal, they wanted as much in a "customs release fee" as the computer was worth so we told them to screw themselves.

What took six months was for us to get DHL to return the thing to us (since we had sent it down with them) without charging for the delivery.

And yes, the customs brokers were very much involved in the scam.

The depressing thing is that they do it because they are poor, but they don't seem to realize that by scamming people trying to bring business to their country they're only destroying their own economy...