MailQ and smtp not working together?

Hi,

I tried to install MailQ on a drupal5 system where smtp was already installed and configured.
After activating the module an error shows up:
Fatal error: Cannot redeclare drupal_mail_wrapper() (previously declared in [...]/htdocs/sites/all/modules/smtp/smtp.module:161) in [...]/htdocs/sites/test.[...]/modules/mailq/mailq.module on line 458
Now I can't deactivate either mailQ nor smtp because all that is rendered and shown up is the error message above. In this case it is just a test instance of a working site, but bad enough, I now have to throw away all recent changes and restart with a cpoy of the working one.

Are there any possibilities in getting those two modules working together?
Or is there functionality duplicated in those modules?
As far as I can see, smtp only uses an external smtp-server for delivering mails (instead of the builtin smtp-functions from php), while MailQ stores outgoing mail in the database and delivers (via the configured delivering way of drupal) this mail with the next cron-run. Is that right? If so, there should not be any contradictory functions in those two modules.

Thanks a lot
XL