Enabling Postfix SMTP Auth using SASL

Has anyone been successful with this? I spent about 8 hours yesterday, working through online HowTos and what not. But was never able to get the SMTP server to accept an AUTH PLAIN. Errors varied depending on the configuration.

This was the most common one:

OTP unavailable because can't read/write key database /etc/opiekeys: No such file or directory

Note that I was able to test my SASL configuration by using the
'testsaslauthd' utility.

So before I go any further I was wondering if it was just broke, or if I have done something wrong.

If you have successfully configured SMTP auth with postfix I would appreciate any pointers and/or configuration hints you can provide.

More than willing to post more of my SASL/SMTPD config files - just let me know what you would like to see.

Thanks
Terry