--- a/server/core.c	2013/07/24 09:49:38	1506473
+++ b/server/core.c	2013/07/24 09:51:14	1506474
@@ -1481,7 +1481,9 @@
             conf->ap_document_root = arg;
         }
         else {
-            return "DocumentRoot must be a directory";
+            return apr_psprintf(cmd->pool, 
+                                "DocumentRoot '%s' is not a directory, or is not readable",
+                                arg);
         }
     }
     return NULL;