Index: /trunk/Mars/CMakeLists.txt
===================================================================
--- /trunk/Mars/CMakeLists.txt	(revision 19346)
+++ /trunk/Mars/CMakeLists.txt	(revision 19347)
@@ -107,6 +107,8 @@
 # --------- ROOT -------------
 
-IF(NOT EXISTS root-config})
-   MESSAGE(WARNING "`root-config` not found in path. First make sure it is accessible.")
+FIND_PROGRAM(ROOTCONFIG_EXECUTALE NAMES root-configx)
+FIND_PACKAGE_HANDLE_STANDARD_ARGS(root-config DEFAULT_MSG ROOTCONFIG_EXECUTABLE)
+IF(NOT ROOTCONFIG_EXECUTABLE)
+   MESSAGE(FATAL_ERROR "Please make sure `root-config` is accessible in your path. In case of an installation from source, you might need to source\n . [path-to-root]/bin/thisroot.sh")
 ENDIF()