fix backup bug
diff --git a/Android.mk b/Android.mk
index 27e1b0c..83cdf9f 100644
--- a/Android.mk
+++ b/Android.mk
@@ -25,7 +25,7 @@
 
 LOCAL_FORCE_STATIC_EXECUTABLE := true
 
-RECOVERY_API_VERSION := 1.5.0
+RECOVERY_API_VERSION := 1.6.0
 LOCAL_CFLAGS += -DRECOVERY_API_VERSION=$(RECOVERY_API_VERSION)
 
 # This binary is in the recovery ramdisk, which is otherwise a copy of root.
diff --git a/extendedcommands.c b/extendedcommands.c
index e7ffb8f..104957a 100644
--- a/extendedcommands.c
+++ b/extendedcommands.c
@@ -334,9 +334,10 @@
     }
 
     char cmd[PATH_MAX];
-    if (NULL == backup_name)
-        backup_name = "";
-    sprintf(cmd, "/sbin/nandroid-mobile.sh backup /sdcard/clockworkmod/backup/ %s", backup_name);
+    if (NULL != backup_name)
+    	sprintf(cmd, "/sbin/nandroid-mobile.sh backup /sdcard/clockworkmod/backup/ %s", backup_name);
+    else
+	sprintf(cmd, "/sbin/nandroid-mobile.sh backup /sdcard/clockworkmod/backup/");
     ui_print("Performing backup...\n");
     int ret = system(cmd);
     if (ret != 0)
@@ -474,4 +475,4 @@
         LOGE("Can't install update commands\n");
     }
     return run_script(argv[1]);
-}
\ No newline at end of file
+}