diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/transport/JschConfigSessionFactory.java b/org.eclipse.jgit/src/org/eclipse/jgit/transport/JschConfigSessionFactory.java
index 0bdd6ba81..79af1ebc6 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/transport/JschConfigSessionFactory.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/transport/JschConfigSessionFactory.java
@@ -551,7 +551,7 @@ public String[] getValues(String key) {
 	 * @param config
 	 *            to use
 	 */
-	void setConfig(OpenSshConfig config) {
+	synchronized void setConfig(OpenSshConfig config) {
 		this.config = config;
 	}
 }