Looks like this part from dchagin's patch

	http://lists.freebsd.org/pipermail/freebsd-emulation/2008-September/005273.html

didn't get applied, at least alpha versions of Linux Firefox 3.7 needs it

	http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/

because of this code:

	http://mxr.mozilla.org/mozilla-central/source/toolkit/crashreporter/google-breakpad/src/client/linux/crash_generation/crash_generation_server.cc#239

That Firefox also needs a small patch to allow setsockopt() with
SOCK_SEQPACKET, I've put that here:

	http://people.freebsd.org/~nox/afunix_seqpacket_sockopt.patch

..and if you aren't running head you also need to merge this commit first:

	http://svn.freebsd.org/viewvc/base?view=revision&revision=197775

I'v put an 8-stable patch for that here:

	http://people.freebsd.org/~nox/afunix_seqpacket-8stable.patch

(But the java plugin still doesn't work, only flash...)

Index: src/sys/amd64/linux32/linux.h
@@ -691,6 +691,7 @@ union l_semun {
 #define	LINUX_SO_NO_CHECK	11
 #define	LINUX_SO_PRIORITY	12
 #define	LINUX_SO_LINGER		13
+#define	LINUX_SO_PASSCRED	16
 #define	LINUX_SO_PEERCRED	17
 #define	LINUX_SO_RCVLOWAT	18
 #define	LINUX_SO_SNDLOWAT	19
Index: src/sys/compat/linux/linux_socket.c
@@ -295,6 +295,8 @@ linux_to_bsd_so_sockopt(int opt)
 		return (SO_OOBINLINE);
 	case LINUX_SO_LINGER:
 		return (SO_LINGER);
+	case LINUX_SO_PASSCRED:
+		return (LOCAL_CREDS);
 	case LINUX_SO_PEERCRED:
 		return (LOCAL_PEERCRED);
 	case LINUX_SO_RCVLOWAT:
@@ -1376,6 +1378,11 @@ linux_setsockopt(struct thread *td, stru
 	switch (bsd_args.level) {
 	case SOL_SOCKET:
 		name = linux_to_bsd_so_sockopt(args->optname);
+		switch (args->optname) {
+		case LINUX_SO_PASSCRED:
+			/* FreeBSD bug? socket level opts at non socket level */			bsd_args.level = 0;
+			break;
+		}
 		switch (name) {
 		case SO_RCVTIMEO:
 			/* FALLTHROUGH */
@@ -1453,6 +1460,11 @@ linux_getsockopt(struct thread *td, stru
 	switch (bsd_args.level) {
 	case SOL_SOCKET:
 		name = linux_to_bsd_so_sockopt(args->optname);
+		switch (args->optname) {
+		case LINUX_SO_PASSCRED:
+			/* FreeBSD bug? socket level opts at non socket level */			bsd_args.level = 0;
+			break;
+		}
 		switch (name) {
 		case SO_RCVTIMEO:
 			/* FALLTHROUGH */
Index: src/sys/i386/linux/linux.h
@@ -667,6 +667,7 @@ union l_semun {
 #define	LINUX_SO_NO_CHECK	11
 #define	LINUX_SO_PRIORITY	12
 #define	LINUX_SO_LINGER		13
+#define	LINUX_SO_PASSCRED	16
 #define	LINUX_SO_PEERCRED	17
 #define	LINUX_SO_RCVLOWAT	18
 #define	LINUX_SO_SNDLOWAT	19