diff --git a/PROBLEMS b/PROBLEMS
index e6eaf2a..e903cec 100644
--- a/PROBLEMS
+++ b/PROBLEMS
@@ -957,3 +957,11 @@ then
   make
 
 as usual.
+
+----------------------------------------------------------------------
+
+* Configuration on MacOS X 10.6 doesn't succeed with the developer-tools
+  shipped native clang (`Apple clang version 1.7 (tags/Apple/clang-77)
+  (based on LLVM 2.9svn)').  It worked successfully with newer compilers
+  tested have been clang(1) version 3.4 (from MacPorts) and gcc(1) (MacPorts
+  gcc48 4.8.2_0) 4.8.2.