diff --git a/java/src/ch/ntb/usb/LibusbJava.java b/java/src/ch/ntb/usb/LibusbJava.java
index 27d5f98..dd6ee65 100644
--- a/java/src/ch/ntb/usb/LibusbJava.java
+++ b/java/src/ch/ntb/usb/LibusbJava.java
@@ -99,7 +99,8 @@ public class LibusbJava {
 	 * 
 	 * @param dev
 	 *            The device to open.
-	 * @return a handle used in future communication with the device.
+	 * @return a handle used in future communication with the device. 0 if an
+	 *         error has occurred.
 	 */
 	public static native int usb_open(Usb_Device dev);