Can you try to add to the file the changes introduced by the referenced commit above, or the diff at:
* https://github.com/kamailio/kamailio/commit/1bba5faf5ced9fdd95446e4ae8913a0c...
I guess that the problem is from the xmlrpc library no longer defining TRUE/FALSE.
Anyhow, if you start fresh, be aware that MI is deprecated and planned to be removed very soon (could happen even before next release). Start using the RPC interface, equivalent module being xmlprc. Or you can use jsonrpc-s.