diff -up ./build.xml.tests-headless ./build.xml --- ./build.xml.tests-headless 2013-07-04 20:42:30.000000000 +0200 +++ ./build.xml 2013-07-05 15:06:19.354441386 +0200 @@ -885,6 +885,7 @@ osname=macosx;processor=x86;processor=x8 <sysproperty key="jna.builddir" file="${build}"/> <sysproperty key="jna.nativedir" file="${build.native}"/> <jvmarg value="${vmopt.arch}"/> + <jvmarg value="-Djava.awt.headless=true"/> <classpath><path refid="test.runpath"/></classpath> <formatter type="brief" usefile="false"/> <formatter type="xml"/>