diff -p -up ppp-2.4.4/pppd/ipcp.c.multipledefrt ppp-2.4.4/pppd/ipcp.c
--- ppp-2.4.4/pppd/ipcp.c.multipledefrt	2005-08-26 01:59:34.000000000 +0200
+++ ppp-2.4.4/pppd/ipcp.c	2008-06-03 10:39:15.000000000 +0200
@@ -196,6 +196,8 @@ static option_t ipcp_option_list[] = {
     { "-defaultroute", o_bool, &ipcp_allowoptions[0].default_route,
       "disable defaultroute option", OPT_ALIAS | OPT_A2CLR,
       &ipcp_wantoptions[0].default_route },
+    { "multipledefaultroutes", o_bool, &ipcp_wantoptions[0].multiple_def_routes,
+      "Add default route even if one already exists", 1 },
 
     { "proxyarp", o_bool, &ipcp_wantoptions[0].proxy_arp,
       "Add proxy ARP entry", OPT_ENABLE|1, &ipcp_allowoptions[0].proxy_arp },
diff -p -up ppp-2.4.4/pppd/ipcp.h.multipledefrt ppp-2.4.4/pppd/ipcp.h
--- ppp-2.4.4/pppd/ipcp.h.multipledefrt	2002-12-05 00:03:32.000000000 +0100
+++ ppp-2.4.4/pppd/ipcp.h	2008-06-03 10:41:46.000000000 +0200
@@ -70,6 +70,7 @@ typedef struct ipcp_options {
     bool old_addrs;		/* Use old (IP-Addresses) option? */
     bool req_addr;		/* Ask peer to send IP address? */
     bool default_route;		/* Assign default route through interface? */
+    bool multiple_def_routes;	/* Allow multiple default routes? */
     bool proxy_arp;		/* Make proxy ARP entry for peer? */
     bool neg_vj;		/* Van Jacobson Compression? */
     bool old_vj;		/* use old (short) form of VJ option? */
diff -p -up ppp-2.4.4/pppd/pppd.8.multipledefrt ppp-2.4.4/pppd/pppd.8
--- ppp-2.4.4/pppd/pppd.8.multipledefrt	2008-06-03 10:35:47.000000000 +0200
+++ ppp-2.4.4/pppd/pppd.8	2008-06-03 10:39:59.000000000 +0200
@@ -120,6 +120,12 @@ Add a default route to the system routin
 the gateway, when IPCP negotiation is successfully completed.
 This entry is removed when the PPP connection is broken.  This option
 is privileged if the \fInodefaultroute\fR option has been specified.
+.B multipledefaultroutes
+This option is a flag to the defaultroute option. If defaultroute is
+set and this flag is also set, pppd will add the new default route
+even if there is already a default route, allowing multiple default
+routes.
+.TP
 .TP
 .B disconnect \fIscript
 Execute the command specified by \fIscript\fR, by passing it to a
diff -p -up ppp-2.4.4/pppd/sys-linux.c.multipledefrt ppp-2.4.4/pppd/sys-linux.c
--- ppp-2.4.4/pppd/sys-linux.c.multipledefrt	2008-06-03 10:35:47.000000000 +0200
+++ ppp-2.4.4/pppd/sys-linux.c	2008-06-03 10:40:14.000000000 +0200
@@ -1588,7 +1588,7 @@ int sifdefaultroute (int unit, u_int32_t
 {
     struct rtentry rt;
 
-    if (defaultroute_exists(&rt) && strcmp(rt.rt_dev, ifname) != 0) {
+    if (!ipcp_wantoptions[0].multiple_def_routes && defaultroute_exists(&rt) && strcmp(rt.rt_dev, ifname) != 0) {
 	if (rt.rt_flags & RTF_GATEWAY)
 	    error("not replacing existing default route via %I",
 		  SIN_ADDR(rt.rt_gateway));