This should fix it:
diff -u --recursive --new-file pre2.0.3/linux/net/unix/af_unix.c linux/net/unix/af_unix.c
--- pre2.0.3/linux/net/unix/af_unix.c Mon May 13 23:02:54 1996
+++ linux/net/unix/af_unix.c Mon May 13 23:02:15 1996
@@ -505,6 +505,7 @@
return err;
skb->sk=sk; /* So they know it is us */
skb->free=1;
+ skb->h.filp=NULL;
sk->state=TCP_CLOSE;
unix_mkname(sunaddr, addr_len);
other=unix_find_other(sunaddr->sun_path, &err);
-----
Linus