Can't send mail with IMP3 RC2

[Kevin W. Brown]

I have installed IMP3 RC2, Horde2 RC2 and PEAR 4.0.7RC3 (from horde.org)  
and I am having trouble sending mail.  After composing a message and
clicking the 'Send Message' button, I get an error at the top of the
compose window that reads 'There was an error sending your message'.  I
have looked through all of my logs, and I can't find anything that would
give me a hint as to why I am getting this error.  Originally, I was
trying to use sendmail, and I had the following lines in my horde.php:

$conf['mailer']['type'] = 'sendmail';
$conf['mailer']['params'] = array('sendmail_path' => '/usr/sbin/sendmail');

That didn't work.

I then changed the above to:

$conf['mailer']['type'] = 'smtp';
$conf['mailer']['params'] = array();

and added

    'smtphost' => 'mail.qis.net',

to my mail server specified in servers.php.

I'm at a loss as to what to do now.  I searched the mailing list archives
to no avail. IMP 2.2.7 works fine on this machine.  Does anyone here have
a suggestion?

Here's some more info on my platform:

Cobalt Linux (Raq4r - kernel 2.2.16)
Apache 1.3.20
PHP 4.0.6
Sendmail 8.10.2

Any help would be greatly appreciated!

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       Kevin W. Brown      | 2975B Manchester Rd. | E-Mail: kevin@qis.net
 Quantum Internet Services | Manchester, MD 21102 |  Voice: 410-239-6920
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