Index: /trunk/src/VBox/Frontends/VBoxManage/VBoxManageGuestProp.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VBoxManage/VBoxManageGuestProp.cpp	(revision 15993)
+++ /trunk/src/VBox/Frontends/VBoxManage/VBoxManageGuestProp.cpp	(revision 15994)
@@ -353,5 +353,5 @@
  * Pack the patterns
  */
-    Utf8Str Utf8Patterns(argc > 2 ? argv[2] : "");
+    Utf8Str Utf8Patterns(argc > 2 ? argv[2] : "*");
     for (ssize_t i = 3; i < argc; ++i)
         Utf8Patterns = Utf8StrFmt ("%s,%s", Utf8Patterns.raw(), argv[i]);
Index: /trunk/src/VBox/Main/MachineImpl.cpp
===================================================================
--- /trunk/src/VBox/Main/MachineImpl.cpp	(revision 15993)
+++ /trunk/src/VBox/Main/MachineImpl.cpp	(revision 15994)
@@ -3170,8 +3170,13 @@
     if (!VALID_PTR (aPatterns) && (aPatterns != NULL))
         return E_POINTER;
-    CheckComArgSafeArrayNotNull (aNames);
-    CheckComArgSafeArrayNotNull (aValues);
-    CheckComArgSafeArrayNotNull (aTimestamps);
-    CheckComArgSafeArrayNotNull (aFlags);
+
+    if (ComSafeArrayOutIsNull (aNames))
+        return E_POINTER;
+    if (ComSafeArrayOutIsNull (aValues))
+        return E_POINTER;
+    if (ComSafeArrayOutIsNull (aTimestamps))
+        return E_POINTER;
+    if (ComSafeArrayOutIsNull (aFlags))
+        return E_POINTER;
 
     AutoCaller autoCaller (this);