The -n option must appear after the iface options, else dhclient 
just prints its help text. Crazy.

RP - 25/5/09

Index: git/plugins/dhclient.c
===================================================================
--- git.orig/plugins/dhclient.c	2009-05-26 00:01:02.000000000 +0100
+++ git/plugins/dhclient.c	2009-05-26 00:01:38.000000000 +0100
@@ -165,18 +165,18 @@
 	argv[0] = DHCLIENT;
 	argv[1] = "-d";
 	argv[2] = "-q";
-	argv[3] = "-n";
-	argv[4] = "-e";
-	argv[5] = address;
-	argv[6] = "-pf";
-	argv[7] = pidfile;
-	argv[8] = "-lf";
-	argv[9] = leases;
-	argv[10] = "-cf";
-	argv[11] = config;
-	argv[12] = "-sf";
-	argv[13] = script;
-	argv[14] = task->ifname;
+	argv[3] = "-e";
+	argv[4] = address;
+	argv[5] = "-pf";
+	argv[6] = pidfile;
+	argv[7] = "-lf";
+	argv[8] = leases;
+	argv[9] = "-cf";
+	argv[10] = config;
+	argv[11] = "-sf";
+	argv[12] = script;
+	argv[13] = task->ifname;
+	argv[14] = "-n";
 	argv[15] = NULL;
 
 	envp[0] = NULL;