Even with java.awt.headless=true, captchas don't work on 1.4.2 or 1.5.

com.octo.captcha.CaptchaException
at com.octo.captcha.image.gimpy.GimpyFactory.getImageCaptcha(GimpyFactory.java:547)
at com.octo.captcha.engine.image.ListImageCaptchaEngine.getNextImageCaptcha(ListImageCaptchaEngine.java:570)
at com.octo.captcha.engine.image.ImageCaptchaEngine.getNextCaptcha(ImageCaptchaEngine.java:94)
at com.octo.captcha.service.EhcacheManageableCaptchaService.generateAndStoreCaptcha(EhcacheManageableCaptchaService.java:822)
at com.octo.captcha.service.AbstractCaptchaService.getChallengeForID(AbstractCaptchaService.java:531)
at com.octo.captcha.service.image.EhcacheManageableImageCaptchaService.getImageChallengeForID(EhcacheManageableImageCaptchaService.java:505)
at com.atlassian.confluence.servlet.ImageCaptchaServlet.doGet(ImageCaptchaServlet.java:48)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.SecurityFilter.doFilter(SecurityFilter.java:182)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.seraph.filter.LoginFilter.doFilter(LoginFilter.java:181)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at com.atlassian.core.filters.gzip.GzipFilter.doFilter(GzipFilter.java:61)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:202)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199)
at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282)
at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:754)
at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:684)
at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:876)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at java.lang.Thread.run(Thread.java:613)
Caused by: java.awt.HeadlessException
at sun.java2d.HeadlessGraphicsEnvironment.getDefaultScreenDevice(HeadlessGraphicsEnvironment.java:65)
at apple.awt.OSXOffScreenSurfaceData.getCopyWithBgColor(OSXOffScreenSurfaceData.java:749)
at apple.awt.OSXSurfaceData.blitImage(OSXSurfaceData.java:1402)
at apple.awt.CRenderer.blitImage(CRenderer.java:698)
at apple.awt.CRenderer.copyImage(CRenderer.java:712)
at apple.awt.CRenderer.copyImage(CRenderer.java:799)
at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3160)
at sun.awt.image.ImageRepresentation.drawToBufImage(ImageRepresentation.java:746)
at apple.awt.OSXImageRepresentation.drawToBufImage(OSXImageRepresentation.java:90)
at apple.awt.CRenderer.copyImage(CRenderer.java:809)
at sun.java2d.pipe.ValidatePipe.copyImage(ValidatePipe.java:168)
at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3160)
at com.octo.captcha.component.image.deformation.ImageDeformationByFilters.deformImage(ImageDeformationByFilters.java:506)
at com.octo.captcha.component.image.wordtoimage.DeformedComposedWordToImage.getImage(DeformedComposedWordToImage.java:580)
at com.octo.captcha.image.gimpy.GimpyFactory.getImageCaptcha(GimpyFactory.java:544)