Use the \note and \warning macros where appropriate.
diff --git a/Doc/lib/libtabnanny.tex b/Doc/lib/libtabnanny.tex
index 238b3b5..7985d9e 100644
--- a/Doc/lib/libtabnanny.tex
+++ b/Doc/lib/libtabnanny.tex
@@ -14,8 +14,8 @@
 However it is possible to import it into an IDE and use the function
 \function{check()} described below.
 
-\strong{Warning:}  The API provided by this module is likely to change 
-in future releases; such changes may not be backward compatible.
+\warning{The API provided by this module is likely to change 
+in future releases; such changes may not be backward compatible.}
 
 \begin{funcdesc}{check}{file_or_dir}
   If \var{file_or_dir} is a directory and not a symbolic link, then