diff --git a/configs/olimex-lpc1766stk/README.txt b/configs/olimex-lpc1766stk/README.txt
index ca878488f60..aba93f829e0 100755
--- a/configs/olimex-lpc1766stk/README.txt
+++ b/configs/olimex-lpc1766stk/README.txt
@@ -601,6 +601,14 @@ Olimex LPC1766-STK Configuration Options
 	CONFIG_UARTn_PARTIY - 0=no parity, 1=odd parity, 2=even parity
 	CONFIG_UARTn_2STOP - Two stop bits
 
+
+  LPC17xx specific PHY/Ethernet device driver settings
+
+	CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+	CONFIG_PHY_AUTONEG - Enable auto-negotion
+	CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+	CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+
   LPC17xx USB Configuration
 
 	CONFIG_LPC17_USBDEV_FRAME_INTERRUPT
diff --git a/configs/olimex-lpc1766stk/include/board.h b/configs/olimex-lpc1766stk/include/board.h
index 0ac0466a862..cf25cfc0cdd 100755
--- a/configs/olimex-lpc1766stk/include/board.h
+++ b/configs/olimex-lpc1766stk/include/board.h
@@ -122,6 +122,11 @@
 #define CONFIG_LP17_FLASH          1
 #define BOARD_FLASHCFG_VALUE       0x0000303a
 
+/* Ethernet configuration */
+
+//#define ETH_MCFG_CLKSEL_DIV ETH_MCFG_CLKSEL_DIV44
+#define ETH_MCFG_CLKSEL_DIV ETH_MCFG_CLKSEL_DIV20
+
 /* LED definitions ******************************************************************/
 
                                       /* LED1 LED2 */
diff --git a/configs/olimex-lpc1766stk/nettest/defconfig b/configs/olimex-lpc1766stk/nettest/defconfig
index 76902eb0ff2..fd1e18d780c 100755
--- a/configs/olimex-lpc1766stk/nettest/defconfig
+++ b/configs/olimex-lpc1766stk/nettest/defconfig
@@ -181,6 +181,19 @@ CONFIG_UART1_2STOP=0
 CONFIG_UART2_2STOP=0
 CONFIG_UART3_2STOP=0
 
+#
+# LPC17xx specific PHY/Ethernet device driver settings
+#
+# CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+# CONFIG_PHY_AUTONEG - Enable auto-negotion
+# CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+# CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+#
+CONFIG_PHY_KS8721=y
+CONFIG_PHY_AUTONEG=y
+CONFIG_PHY_SPEED100=n
+CONFIG_PHY_FDUPLEX=y
+
 #
 # General build options
 #
diff --git a/configs/olimex-lpc1766stk/nsh/defconfig b/configs/olimex-lpc1766stk/nsh/defconfig
index 9d1486d7fb0..cf612d47cd7 100755
--- a/configs/olimex-lpc1766stk/nsh/defconfig
+++ b/configs/olimex-lpc1766stk/nsh/defconfig
@@ -181,6 +181,19 @@ CONFIG_UART1_2STOP=0
 CONFIG_UART2_2STOP=0
 CONFIG_UART3_2STOP=0
 
+#
+# LPC17xx specific PHY/Ethernet device driver settings
+#
+# CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+# CONFIG_PHY_AUTONEG - Enable auto-negotion
+# CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+# CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+#
+CONFIG_PHY_KS8721=y
+CONFIG_PHY_AUTONEG=y
+CONFIG_PHY_SPEED100=n
+CONFIG_PHY_FDUPLEX=y
+
 #
 # General build options
 #
diff --git a/configs/olimex-lpc1766stk/ostest/defconfig b/configs/olimex-lpc1766stk/ostest/defconfig
index 29daca2b685..76fb011988d 100755
--- a/configs/olimex-lpc1766stk/ostest/defconfig
+++ b/configs/olimex-lpc1766stk/ostest/defconfig
@@ -181,6 +181,19 @@ CONFIG_UART1_2STOP=0
 CONFIG_UART2_2STOP=0
 CONFIG_UART3_2STOP=0
 
+#
+# LPC17xx specific PHY/Ethernet device driver settings
+#
+# CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+# CONFIG_PHY_AUTONEG - Enable auto-negotion
+# CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+# CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+#
+CONFIG_PHY_KS8721=y
+CONFIG_PHY_AUTONEG=y
+CONFIG_PHY_SPEED100=n
+CONFIG_PHY_FDUPLEX=y
+
 #
 # General build options
 #
diff --git a/configs/olimex-lpc1766stk/usbserial/defconfig b/configs/olimex-lpc1766stk/usbserial/defconfig
index e06fa3a9889..7d5f2dd6c2e 100755
--- a/configs/olimex-lpc1766stk/usbserial/defconfig
+++ b/configs/olimex-lpc1766stk/usbserial/defconfig
@@ -181,6 +181,19 @@ CONFIG_UART1_2STOP=0
 CONFIG_UART2_2STOP=0
 CONFIG_UART3_2STOP=0
 
+#
+# LPC17xx specific PHY/Ethernet device driver settings
+#
+# CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+# CONFIG_PHY_AUTONEG - Enable auto-negotion
+# CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+# CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+#
+CONFIG_PHY_KS8721=y
+CONFIG_PHY_AUTONEG=y
+CONFIG_PHY_SPEED100=n
+CONFIG_PHY_FDUPLEX=y
+
 #
 # General build options
 #
diff --git a/configs/olimex-lpc1766stk/usbstorage/defconfig b/configs/olimex-lpc1766stk/usbstorage/defconfig
index d62bfd55c4f..f1befb4460e 100755
--- a/configs/olimex-lpc1766stk/usbstorage/defconfig
+++ b/configs/olimex-lpc1766stk/usbstorage/defconfig
@@ -181,6 +181,19 @@ CONFIG_UART1_2STOP=0
 CONFIG_UART2_2STOP=0
 CONFIG_UART3_2STOP=0
 
+#
+# LPC17xx specific PHY/Ethernet device driver settings
+#
+# CONFIG_PHY_KS8721 - Selects Micrel KS8721 PHY
+# CONFIG_PHY_AUTONEG - Enable auto-negotion
+# CONFIG_PHY_SPEED100 - Select 100Mbit vs. 10Mbit speed.
+# CONFIG_PHY_FDUPLEX - Select full (vs. half) duplex
+#
+CONFIG_PHY_KS8721=y
+CONFIG_PHY_AUTONEG=y
+CONFIG_PHY_SPEED100=n
+CONFIG_PHY_FDUPLEX=y
+
 #
 # General build options
 #