Updated runtime files.
diff --git a/runtime/doc/message.txt b/runtime/doc/message.txt
index c4ed18b..d534cab 100644
--- a/runtime/doc/message.txt
+++ b/runtime/doc/message.txt
@@ -1,4 +1,4 @@
-*message.txt* For Vim version 7.3c. Last change: 2010 Jul 20
+*message.txt* For Vim version 7.3c. Last change: 2010 Jul 26
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -467,7 +467,16 @@
is consuming your memory. Be careful! Vim is not completely prepared for an
out-of-memory situation. First make sure that any changes are saved. Then
try to solve the memory shortage. To stay on the safe side, exit Vim and
-start again. Also see |msdos-limitations|.
+start again.
+
+Buffers are only partly kept in memory, thus editing a very large file is
+unlikely to cause an out-of-memory situation. Undo information is completely
+in memory, you can reduce that with these options:
+- 'undolevels' Set to a low value, or to -1 to disable undo completely. This
+ helps for a change that affects all lines.
+- 'undoreload' Set to zero to disable.
+
+Also see |msdos-limitations|.
*E339* >
Pattern too long