I've had exactly the same problem. Thanks to you, I searched the report sourcefile for empty font tags, and there were quite a lot. Also, the compiler throwed exceptions with some other fonts, which actually was not in the JVM. So, instead of setting the ignore flag, i used a texteditor and replaced these tags with fontName="Verdana", which is present at my system. I think it's a bug in JasperReports 4.x, and not in iReport, since I actually had these empty tags in earlier versions of the same report. And they were appearently ignored and substituted with another present font. Now, it works fine. But of course, I do not have thousands of files to edit:-) I look forward to a new release of JasperReport where this bug is fixed:-)
