diff --git a/src/support/docstring.C b/src/support/docstring.C
index 68bb11b417..5e8d05f715 100644
--- a/src/support/docstring.C
+++ b/src/support/docstring.C
@@ -470,9 +470,9 @@ protected:
 			s += static_cast<char>(*iit);
 		// We add another character, not part of the numpunct facet,
 		// in order to avoid setting the eofbit in the stream state,
-		// which would prevent any further read. The '\0' seems a
+		// which would prevent any further read. The space seems a
 		// good choice here.
-		s += '\0';
+		s += ' ';
 		string_num_get_facet f;
 		f.get(s.begin(), s.end(), b, err, v);