BUG: fix for bug 1838

Source/cmAddTestCommand.h

@@ -67,7 +67,9 @@ public:
       "The tests are run by the testing subsystem by executing Exename "
       "with the specified arguments.  Exename can be either an executable "
       "built by built by this project or an arbitrary executable on the "
-      "system (like tclsh).";
+      "system (like tclsh).  The test will be run with the current working "
+      "directory set to the CMakeList.txt files corresponding directory "
+      "in the binary tree.";
     }
   
   cmTypeMacro(cmAddTestCommand, cmCommand);