[imp] Help with enabling spam reporting

[HiP-HiPpO]

>> I created the file imp/conf/backends.local.php with only the  
>> following contents. When logging in, I see no additional option to  
>> report mail as spam. How do I enable reporting?
>>
>> <?php
>> $conf['spam']['reporting'] = true;
>> $conf['spam']['spamfolder'] = Spam;
>> $conf['notspam']['reporting'] = true;
>> $conf['notspam']['spamfolder'] = Inbox;
>> $conf['spam']['program'] = '/usr/bin/spamc -C report -u %l';
>> $conf['notspam']['program'] = '/usr/bin/spamc -C revoke -u %l';
>>
>> Horde version 5.2.12
>> Imp version 6.2.16
>>
>> Thank you, Art
>> -
>
>   I replaced all the contents in backends.local.php with the example  
> shown in this thread and I have spam reporting buttons
> https://lists.horde.org/archives/horde/Week-of-Mon-20150216/053728.html

This does not seem to be working.  Initially, I was able to select a  
few incoming messages and choose the Spam button to report.  This is  
no longer working.  Now I select only one message, choose "Report as  
Spam".  The message is updated with an icon to suggest it is being  
processed as spam, however, that process never completes and the  
logged in session is hung in the browser.  I need to kill the browser  
and relogin to find that one message in an unchanged state, still seen  
as New in the Inbox.