Fix ServiceMayNotContinueException constructors for Java 1.5

IOException did not add a (String, Throwable) constructor until 1.5.
Instead use the String super constructor and initCause to initialize
the exception.

Fixes bug 418889

Change-Id: Ide735ecfc7d04884981b79b57a4275863ce17006

org.eclipse.jgit/src/org/eclipse/jgit/transport/ServiceMayNotContinueException.java

@@ -79,7 +79,8 @@ public class ServiceMayNotContinueException extends IOException {
 	 *            the cause of the exception.
 	 */
 	public ServiceMayNotContinueException(String msg, Throwable cause) {
-		super(msg, cause);
+		super(msg);
+		initCause(cause);
 	}
 
 	/**
@@ -89,7 +90,7 @@ public class ServiceMayNotContinueException extends IOException {
 	 *            the cause of the exception.
 	 */
 	public ServiceMayNotContinueException(Throwable cause) {
-		super(JGitText.get().internalServerError, cause);
+		this(JGitText.get().internalServerError, cause);
 	}
 
 	/** @return true if the message was already output to the client. */