diff -Nru linux-2.6.18.orig/drivers/usb/serial/pl2303.c linux-2.6.18/drivers/usb/serial/pl2303.c
--- linux-2.6.18.orig/drivers/usb/serial/pl2303.c	2007-08-24 00:10:40.000000000 +0200
+++ linux-2.6.18/drivers/usb/serial/pl2303.c	2007-08-24 00:11:22.000000000 +0200
@@ -73,6 +73,7 @@
 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
 	{ USB_DEVICE(NOKIA_CA42_VENDOR_ID, NOKIA_CA42_PRODUCT_ID) },
 	{ USB_DEVICE(CA_42_CA42_VENDOR_ID, CA_42_CA42_PRODUCT_ID) },
diff -Nru linux-2.6.18.orig/drivers/usb/serial/pl2303.h linux-2.6.18/drivers/usb/serial/pl2303.h
--- linux-2.6.18.orig/drivers/usb/serial/pl2303.h	2007-08-24 00:10:40.000000000 +0200
+++ linux-2.6.18/drivers/usb/serial/pl2303.h	2007-08-24 00:11:22.000000000 +0200
@@ -59,6 +59,7 @@
 #define SIEMENS_PRODUCT_ID_SX1	0x0001
 #define SIEMENS_PRODUCT_ID_X65	0x0003
 #define SIEMENS_PRODUCT_ID_X75	0x0004
+#define SIEMENS_PRODUCT_ID_EF81	0x0005
 
 #define SYNTECH_VENDOR_ID	0x0745
 #define SYNTECH_PRODUCT_ID	0x0001