diff -urN busybox-1.11.2-orig/networking/udhcp/clientpacket.c busybox-1.11.2/networking/udhcp/clientpacket.c
--- busybox-1.11.2-orig/networking/udhcp/clientpacket.c	2010-05-19 14:15:31.000000000 +0800
+++ busybox-1.11.2/networking/udhcp/clientpacket.c	2010-05-18 17:36:37.000000000 +0800
@@ -46,6 +46,8 @@
 		add_option_string(packet->options, client_config.clientid);
 	if (client_config.hostname)
 		add_option_string(packet->options, client_config.hostname);
+	if (client_config.domain)
+		add_option_string(packet->options, client_config.domain);
 	if (client_config.fqdn)
 		add_option_string(packet->options, client_config.fqdn);
 	if ((type != DHCPDECLINE) && (type != DHCPRELEASE))
	
	
diff -urN busybox-1.11.2-orig/networking/udhcp/dhcpc.c busybox-1.11.2/networking/udhcp/dhcpc.c
--- busybox-1.11.2-orig/networking/udhcp/dhcpc.c	2010-05-19 14:15:31.000000000 +0800
+++ busybox-1.11.2/networking/udhcp/dhcpc.c	2010-05-19 14:05:09.000000000 +0800
@@ -125,7 +125,7 @@
 int udhcpc_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	uint8_t *temp, *message;
-	char *str_c, *str_V, *str_h, *str_F, *str_r;
+	char *str_c, *str_V, *str_h, *str_D, *str_F, *str_r;
 	USE_FEATURE_UDHCP_PORT(char *str_P;)
 	llist_t *list_O = NULL;
 	int tryagain_timeout = 20;
@@ -151,6 +151,7 @@
 		"clientid-none\0"  No_argument       "C"
 		"vendorclass\0"    Required_argument "V"
 		"hostname\0"       Required_argument "H"
+		"domian\0"         Required_argument "D"
 		"fqdn\0"           Required_argument "F"
 		"interface\0"      Required_argument "i"
 		"now\0"            No_argument       "n"
@@ -177,7 +178,7 @@
 		OPT_C = 1 << 1,
 		OPT_V = 1 << 2,
 		OPT_H = 1 << 3,
-		OPT_h = 1 << 4,
+		OPT_D = 1 << 4,
 		OPT_F = 1 << 5,
 		OPT_i = 1 << 6,
 		OPT_n = 1 << 7,
@@ -214,11 +215,11 @@
 	/* Cc: mutually exclusive; O: list; -T,-t,-A take numeric param */
 	opt_complementary = "c--C:C--c:O::T+:t+:A+";
 	USE_GETOPT_LONG(applet_long_options = udhcpc_longopts;)
-	opt = getopt32(argv, "c:CV:H:h:F:i:np:qRr:s:T:t:vSA:O:of"
+	opt = getopt32(argv, "c:CV:H:D:F:i:np:qRr:s:T:t:vSA:O:of"
 		USE_FOR_MMU("b")
 		USE_FEATURE_UDHCPC_ARPING("a")
 		USE_FEATURE_UDHCP_PORT("P:")
-		, &str_c, &str_V, &str_h, &str_h, &str_F
+		, &str_c, &str_V, &str_h, &str_D, &str_F
 		, &client_config.interface, &client_config.pidfile, &str_r /* i,p */
 		, &client_config.script /* s */
 		, &discover_timeout, &discover_retries, &tryagain_timeout /* T,t,A */
@@ -229,8 +230,10 @@
 		client_config.clientid = alloc_dhcp_option(DHCP_CLIENT_ID, str_c, 0);
 	if (opt & OPT_V)
 		client_config.vendorclass = alloc_dhcp_option(DHCP_VENDOR, str_V, 0);
-	if (opt & (OPT_h|OPT_H))
+	if (opt & OPT_H)
 		client_config.hostname = alloc_dhcp_option(DHCP_HOST_NAME, str_h, 0);
+	if (opt & OPT_D)
+		client_config.domain = alloc_dhcp_option(DHCP_DOMAIN_NAME, str_D, 0);
 	if (opt & OPT_F) {
 		client_config.fqdn = alloc_dhcp_option(DHCP_FQDN, str_F, 3);
 		/* Flags: 0000NEOS
		
		
diff -urN busybox-1.11.2-orig/networking/udhcp/dhcpc.h busybox-1.11.2/networking/udhcp/dhcpc.h
--- busybox-1.11.2-orig/networking/udhcp/dhcpc.h	2008-06-25 20:51:14.000000000 +0800
+++ busybox-1.11.2/networking/udhcp/dhcpc.h	2010-05-18 17:37:26.000000000 +0800
@@ -22,6 +22,7 @@
 	uint8_t *clientid;              /* Optional client id to use */
 	uint8_t *vendorclass;           /* Optional vendor class-id to use */
 	uint8_t *hostname;              /* Optional hostname to use */
+	uint8_t *domain;              /* Optional Domainname to use */
 	uint8_t *fqdn;                  /* Optional fully qualified domain name to use */
 };
