install-grinder failure: "The widget (of type 'Button' and with mnemonic 'Finish' and with style 'SWT.PUSH') was not enabled."

12:14:33 Caused by: org.eclipse.swtbot.swt.finder.widgets.TimeoutException: 
Timeout after: 5000 ms.: 
The widget (of type 'Button' and with mnemonic 'Finish' and with 
style 'SWT.PUSH') was not enabled.

12:14:33 Testcase: testInstall took 103.682 sec
12:14:33 	Caused an ERROR
12:14:33 Internal error
12:14:33 java.lang.RuntimeException: Internal error
12:14:33 	at org.jboss.tools.tests.installation.InstallTest.continueInstall(InstallTest.java:213)
12:14:33 	at org.jboss.tools.tests.installation.InstallTest.continueInstall(InstallTest.java:147)
12:14:33 	at org.jboss.tools.tests.installation.InstallTest.installFromSite(InstallTest.java:133)
12:14:33 	at org.jboss.tools.tests.installation.InstallTest.testInstall(InstallTest.java:78)
12:14:33 	at org.eclipse.swtbot.swt.finder.junit.internal.CapturingFrameworkMethod.invokeExplosively(CapturingFrameworkMethod.java:47)
12:14:33 	at org.eclipse.swtbot.swt.finder.junit.SWTBotJunit4ClassRunner.runChild(SWTBotJunit4ClassRunner.java:76)
12:14:33 	at org.eclipse.swtbot.swt.finder.junit.SWTBotJunit4ClassRunner.run(SWTBotJunit4ClassRunner.java:61)
12:14:33 	at org.eclipse.swtbot.eclipse.junit.headless.EclipseTestRunner.run(EclipseTestRunner.java:350)
12:14:33 	at org.eclipse.swtbot.eclipse.junit.headless.EclipseTestRunner.run(EclipseTestRunner.java:208)
12:14:33 	at org.eclipse.swtbot.eclipse.junit.headless.UITestApplication.runTests(UITestApplication.java:117)
12:14:33 	at org.eclipse.e4.ui.internal.workbench.swt.E4Testable$1.run(E4Testable.java:73)
12:14:33 	at java.lang.Thread.run(Thread.java:745)
12:14:33 Caused by: org.eclipse.swtbot.swt.finder.widgets.TimeoutException: Timeout after: 5000 ms.: The widget (of type 'Button' and with mnemonic 'Finish' and with style 'SWT.PUSH') was not enabled.
12:14:33 	at org.eclipse.swtbot.swt.finder.SWTBotFactory.waitUntil(SWTBotFactory.java:522)
12:14:33 	at org.eclipse.swtbot.swt.finder.SWTBotFactory.waitUntil(SWTBotFactory.java:496)
12:14:33 	at org.eclipse.swtbot.swt.finder.SWTBotFactory.waitUntil(SWTBotFactory.java:484)
12:14:33 	at org.eclipse.swtbot.swt.finder.widgets.AbstractSWTBot.waitForEnabled(AbstractSWTBot.java:650)
12:14:33 	at org.eclipse.swtbot.swt.finder.widgets.SWTBotButton.click(SWTBotButton.java:65)
12:14:33 	at org.jboss.tools.tests.installation.InstallTest.continueInstall(InstallTest.java:154)