There are two places to look for debug information, on the client side (browser), by opening the javascript console (chrome, firefox, safari and I think even latest IE all include a debug/javascript console by default). Open it up and attempt a transfer to voicemail and look at the browser console to see if an action is being delivered to the server.
The other part is the server side, you can start fop2_server with debug enabled to have a log file, to do so, edit /etc/sysconfig/fop2 and add "-X 511 -l /var/log" to your current OPTIONS line (that means that you must leave whatever you have already defined and add the aforementioned parameters). So, the OPTIONS line should end up looking something similar to this:
[fixed]
OPTIONS="-d -X 511 -l /var/log"
[/fixed]
Then restart FOP2 with the command
[fixed]
service fop2 restart
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Then, when you attempt a transfer to voicemail, inspect the /var/log/fop2_debug.log and search for the string 'tovoicemail' and look all of the events/messages that happens after that.
Best regards,
