diff --git a/org.eclipse.help.base/src/org/eclipse/help/internal/server/JettyHelpServer.java b/org.eclipse.help.base/src/org/eclipse/help/internal/server/JettyHelpServer.java
index 6d70a7e..d04219d 100644
--- a/org.eclipse.help.base/src/org/eclipse/help/internal/server/JettyHelpServer.java
+++ b/org.eclipse.help.base/src/org/eclipse/help/internal/server/JettyHelpServer.java
@@ -91,6 +91,7 @@
 		public void run() {
 			try {
 				JettyConfigurator.stopServer(webappName);
+				port = -1;
 			} catch (Throwable t) {
 				setException(t); 
 			}