Tomcat 6 java 1.7 Fop 1.1 xmlgraphics-commons-1.5.jar <fo:external-graphic src="file:logotypes/{head/logotype}" width="auto" height="auto" content-width="80%" content-height="auto" /> will produce: org.apache.fop.render.rtf.rtflib.rtfdoc.RtfExternalGraphic$ExternalGraphicException: The tag <fo:external-graph ic> does not support gif - image type both for PNG and GIF files when producing RTF documents The same environment and XSL produce PDF that are ok. Switching back to fop 1.0 and xmlgraphics-commons-1.4.jar resolves the problem.
Do you have jai-imageio.jar in the Tomcat classpath? If not can you try adding that to see if the issue is resolved?
Adding jai_imageio_windows-i586.jar to the Tomcat classpath does make it work. Sorry if I posted an unnecessary bug here. I was not aware that you needed to add jai_image when upgrading from fop 1.0 to fop 1.1