I have downloaded audible software to my Curve. When it attempts to login to Audible to verify, i keep getting a "tunnel failed" message. I have done everything audible suggests. No success. Does anyone have any experience with this or any ideas?

I have a Blackberry Bold and loaded Audibleair, I have the same connection failure problem you described. I connect through a BES server at work and spent some time with our technical support staff. They couldn't get it to work either.

I thought that maybe it had something to do with the cell network so I tried a wi-fi only connection. Audible connected and I was able to login and download books. Our support tech does not know why this works and the connection through the cellular network didn't. I was also able to connect from my home wi-fi network.

I don't don't know why this works? So if you have wi-fi you should be able to use that.

The following link has an explanation. It is not as complete as it could be but indicates why this doesn't work through the cellular connection:
http://audible.custhelp.com/cgi-bin/...810548&p_olh=0

*** Quote from the link above ***
Verifying connection to BlackBerry Enterprise Server
Note: If your Blackberry Smartphone is connected to an Enterprise Server, you will be unable to download most of your content via AudibleAir. AudibleAir is designed to use the WAP browser on your blackberry. However, if you are connected to an Enterprise server, AudibleAir is blocked from using the WAP browser and redirected to the MDS browser. Consequently, the MDS browser has a maximum download limit of 1MB, which is smaller than all of the download segment sizes in AudibleAir.

The change in settings within AudibleAir from Wifi to Cellular fixed the problem for me. Thanks so much! I'm so happy I can use Audible on my Bold!