The ScreenshotApplet class fails to compile under OpenJDK as it depends on com.sun.* classes:

$ mvn clean install
.....
.....
[INFO] [compiler:compile]
[INFO] Compiling 3929 source files to /home/jturner/src/atlassian/jira-trunk/target/classes
[INFO] ------------------------------------------------------------------------
[ERROR] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Compilation failure

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[9,31] com.sun.image.codec.jpeg.JPEGCodec is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[10,31] com.sun.image.codec.jpeg.JPEGEncodeParam is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[11,31] com.sun.image.codec.jpeg.JPEGImageEncoder is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[4,31] com.sun.image.codec.jpeg.ImageFormatException is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[5,31] com.sun.image.codec.jpeg.JPEGCodec is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[6,31] com.sun.image.codec.jpeg.JPEGImageEncoder is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[607,16] com.sun.image.codec.jpeg.JPEGImageEncoder is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[607,43] com.sun.image.codec.jpeg.JPEGCodec is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[608,16] com.sun.image.codec.jpeg.JPEGEncodeParam is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/screenshot/applet/ScreenshotApplet.java:[612,23] cannot find symbol
symbol : method setJPEGEncodeParam(com.sun.image.codec.jpeg.JPEGEncodeParam)
location: class com.sun.image.codec.jpeg.JPEGImageEncoder

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[34,16] com.sun.image.codec.jpeg.JPEGImageEncoder is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[34,47] com.sun.image.codec.jpeg.JPEGCodec is Sun proprietary API and may be removed in a future release

/home/jturner/src/atlassian/jira-trunk/src/java/com/atlassian/jira/servlet/CaptchaServlet.java:[61,15] com.sun.image.codec.jpeg.ImageFormatException is Sun proprietary API and may be removed in a future release

[INFO] ------------------------------------------------------------------------
[INFO] For more information, run Maven with the -e switch
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 19 minutes 13 seconds
[INFO] Finished at: Wed Jun 24 13:14:39 EST 2009
[INFO] Final Memory: 41M/187M
[INFO] ------------------------------------------------------------------------