Specifying headers for DBus Interfaces and Adaptors?

[StoatPatronus]

Qt Creator project files support DBUS_ADAPTORS and DBUS_INTERFACES options which automatically generate DBus adaptors and interfaces from a given XML file.

It does this by running qdbusxml2cpp with the appropriate options. However, my code requires me to include another header file. I can run the qdbusxml2cpp manually with the -i option to include any headers I want, which works great. But I can't do that when I use my .pro file.

Is there anyway to specify the headers? The DBUS_INTERFACES and DBUS_ADAPTORS options aren't even listed in http://doc.qt.io/qt-5/qmake-variable-reference.html