permission denied : XML RPC : adding database to subscription

[HirvisimM]

Hello colleagues,

I'm trying to add databases on existent subscription via Plesk (version 11) XML RPC.
For the request were used the creadentials of the customer the target subscription belongs to. As respone I've got „permission denied“.

To create the databases I had used this XML RPC call :

<packet version="1.6.3.0">
<database>
<add-db>
<webspace-id>ID</webspace-id>
<name>NAME</name>
<type>mysql</type>
</add-db>
</database>
</packet>

After a while of trouble shooting I figured out, that the customer (subscription owner) which creadentials were used for XML RPC call, has no „remote_access_interface“ permission activated.

With creadentials of my reseller account (which has "remote_access_interface“ permission) I tried to activate this permission for subscription-customer with following request, which was confirmed by ok-status:

<packet version="1.4.1.2">
<client>
<set>
<filter>
<login>CLIENT_LOGIN</login>
<filter>
<values>
<permissions>
<remote_access_interface>true</remote_access_interface>
</permissions>
</values>
</set>
</client>
</packet>

After above call the permissions were checked again in order to determine that the „remote_access_interface“-permission has been activated.
Unfortunately, I saw that the call had no effect, even though the call was marked by Plesk as successful (ok-status).

Also in backend as reseller I had found no way to activate this right for the customer.

Is this permission necessary for creation of databases via XML RPC ?
If so, how this right can be activated via XML RPC for subscription customer (my reseller account has this permission activated) ?

Is there another way to create databases as _a reseller for subscriptions_ or _as a customer for his own subscription_ ?
I mean another remote accessible API - without need for human interaction.

my desired processing is :
1. creating customer (call successful with creadentials of reseller)
2. creating subscription for customer (call successful with creadentials of reseller)
3. creating databases for subscription (call failed „permission denied.“ with creadentials of customer (subscription owner) )
4. creating db user (not tested yet)

Thank you.