diff --git a/Documentation/networking/cxacru-cf.py b/Documentation/networking/cxacru-cf.py
new file mode 100644
index 0000000..b41d298
--- /dev/null
+++ b/Documentation/networking/cxacru-cf.py
@@ -0,0 +1,48 @@
+#!/usr/bin/env python
+# Copyright 2009 Simon Arlott
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the Free
+# Software Foundation; either version 2 of the License, or (at your option)
+# any later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+# more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# this program; if not, write to the Free Software Foundation, Inc., 59
+# Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+#
+# Usage: cxacru-cf.py < cxacru-cf.bin
+# Output: values string suitable for the sysfs adsl_config attribute
+#
+# Warning: cxacru-cf.bin with MD5 hash cdbac2689969d5ed5d4850f117702110
+# contains mis-aligned values which will stop the modem from being able
+# to make a connection. If the first and last two bytes are removed then
+# the values become valid, but the modulation will be forced to ANSI
+# T1.413 only which may not be appropriate.
+#
+# The original binary format is a packed list of le32 values.
+
+import sys
+import struct
+
+i = 0
+while True:
+	buf = sys.stdin.read(4)
+
+	if len(buf) == 0:
+		break
+	elif len(buf) != 4:
+		sys.stdout.write("\n")
+		sys.stderr.write("Error: read {0} not 4 bytes\n".format(len(buf)))
+		sys.exit(1)
+
+	if i > 0:
+		sys.stdout.write(" ")
+	sys.stdout.write("{0:x}={1}".format(i, struct.unpack("<I", buf)[0]))
+	i += 1
+
+sys.stdout.write("\n")