diff --git a/ChangeLog b/ChangeLog
index ddba3f052..6018e6cc8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2008-11-14  Robert Millan  <rmh@aybabtu.com>
+
+	* term/i386/pc/serial.c [! GRUB_MACHINE_PCBIOS]
+	(GRUB_SERIAL_PORT_NUM): Fix misscalculation.
+
 2008-11-12  Robert Millan  <rmh@aybabtu.com>
 
 	Make loader/i386/linux.c buildable on i386-pc (although disabled).
diff --git a/term/i386/pc/serial.c b/term/i386/pc/serial.c
index 612492206..4cca42f46 100644
--- a/term/i386/pc/serial.c
+++ b/term/i386/pc/serial.c
@@ -70,7 +70,7 @@ static const unsigned short *serial_hw_io_addr = (const unsigned short *) 0x0400
 #define GRUB_SERIAL_PORT_NUM 4
 #else
 static const unsigned short serial_hw_io_addr[] = { 0x3f8, 0x2f8, 0x3e8, 0x2e8 };
-#define GRUB_SERIAL_PORT_NUM (sizeof(serial_hw_io_addr)/(serial_hw_io_addr[0]))
+#define GRUB_SERIAL_PORT_NUM (sizeof(serial_hw_io_addr)/sizeof(serial_hw_io_addr[0]))
 #endif
 
 /* Return the port number for the UNITth serial device.  */