When I want to render a graphic inside a box with the following properties : <fo:external-graphic src="graph.png" width="4in" border-color="black" border-width="thin" border-style="solid"/> the box is missing despite you mention that FOP is full compliant with these properties.
Works in FOP Trunk (development code) available through SVN. Won't be fixed in FOP 0.20.5.
batch transition pre-FOP1.0 resolved+fixed bugs to closed+fixed