Using user_add function from remote Framework

[catdude]

I have created a client, "Dan M test", on my ISPConfig machine. This client was assigned client #462. I am calling the SOAP interface with:

$params = array ( 'sid' => $session_id,
'module' => 'web',
'function' => 'web_get',
'params' => array( web_title => 'varmints.us', // Reseller1, admin, all
));

and getting back:
Array
(
[web_title] => varmints.us
[doc_id] => 382
[doctype_id] => 1013
[web_host] => www
[web_domain] => varmints.us
<snipped for space>
[web_ip] => 69.66.1.24
[server_id] => 1
[optionen_mysql_user] => web382
[optionen_mysql_passwort] =>
<snipped for space>
[web_id] => 382
)

I also defined an e-mail address, dan@varmints.us. I can fetch this user's settings using:
$params = array ( 'sid' => $session_id,
'module' => 'web',
'function' => 'user_get',
'params' => array( user_username => 'varmints.us_dan', // Reseller1, admin, all
));
which returns:
Array
(
[doc_id] => 362
[doctype_id] => 1014
[user_username] => varmints.us_dan
[user_passwort] =>
<snipped for space>
[user_name] => Dan M
[status] =>
<snip>
[user_id] => 362
)

Now I am trying to add an e-mail address, test@varmints.us. The code I'm trying to use is:
$params = array( 'sid' => $session_id, 'module' => 'web',
'function' => 'user_add',
'params' => array(
web_id => 382,
user_username => 'varmints.us_test',
user_name => 'test',
user_email => 'test',
user_passwort => 'test',
user_speicher => 100,
user_mailquota => 100 ,
user_admin => 0
));
When I run this code it does not produce an error message. However, when I log into ISPConfig and look at varmints.us I only see the dan@varmints.us user. I get the same result if I replace web_id => 382 with web_title => 'varmints.us'.

It appears that I'm misunderstanding something about the user_add function. Could someone please tell me what I'm doing wrong?