diff --git a/doc/Cabal.xml b/doc/Cabal.xml
index c3f4824dd6e7bb2eb0c2d21b09cd577477517f0d..c5bc46cf06ac9a409d40f76e9935c2851dbdad7b 100644
--- a/doc/Cabal.xml
+++ b/doc/Cabal.xml
@@ -298,8 +298,9 @@ Executable program2
         usually the package name, and some of the tools that operate
         on Cabal packages require this.</para>
 
-      <para>In the package description file, lines beginning with
-      <quote><literal>--</literal></quote> are treated as comments
+      <para>In the package description file, lines whose first
+      non-whitespace characters
+      are <quote><literal>--</literal></quote> are treated as comments
       and ignored.</para>
 
       <para>This file should contain of a number global property