diff --git a/ChangeLog b/ChangeLog
index 128c5f959..ddebabefc 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2010-10-17  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* docs/grub.texi (GNU/Linux): Document APM unavailability with
+	32-bit linux protocol.
+
 2010-10-17  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/kern/i386/pc/startup.S (grub_console_setcursor): Check
diff --git a/docs/grub.texi b/docs/grub.texi
index a04e31605..751dd9dc2 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -895,6 +895,14 @@ grub> @kbd{linux /vmlinuz root=/dev/sda1 acpi=off}
 See the documentation in the Linux source tree for complete information on
 the available options.
 
+With @command{linux} GRUB uses 32-bit protocol. Some BIOS services like APM
+or EDD aren't available with this protocol. In this case you need to use
+@command{linux16}
+
+@example
+grub> @kbd{linux16 /vmlinuz root=/dev/sda1 acpi=off}
+@end example 
+
 @item
 If you use an initrd, execute the command @command{initrd} (@pxref{initrd})
 after @command{linux}:
@@ -903,6 +911,12 @@ after @command{linux}:
 grub> @kbd{initrd /initrd}
 @end example
 
+If you used @command{linux16} you need to use @command{initrd16}:
+
+@example
+grub> @kbd{initrd16 /initrd}
+@end example
+
 @item
 Finally, run the command @command{boot} (@pxref{boot}).
 @end enumerate