Deploy custom widgets on harmattan 1.2

[dvdk]

I have a Qt application that uses QUiLoader to load .ui files that describe the user interface. Some .ui files also use custom widgets built as QtDesigner plugins. This works as expected on the Desktop.
But now I want to deploy the application on Harmattan platform (currently using qemu image), all seems to work fine (though very slow in qemu) except I can't seem to figure out how to build and deploy the custom widgets for the Harmattan platform.

I use QtSDK v1.1.4, and the harmattan build directory doesn't seem to have the QtDesigner includes/libs (as confirmed here : http://developer.qt.nokia.com/forums/viewthread/362/ )

So it fails at building the target with :

@fatal error: QtDesigner/QDesignerExportWidget: No such file or directory@

I can build the custom widget if I remove all QDesigner dependencies, but obviously the plugin is not loaded by QUiLoader when needed.

So my question is : How can I create qt widget plugins that don't depend upon the QDesigner module?