diff --git a/usr/kinit/nfsmount/sunrpc.c b/usr/kinit/nfsmount/sunrpc.c
index 915d412..6607cf7 100644
--- a/usr/kinit/nfsmount/sunrpc.c
+++ b/usr/kinit/nfsmount/sunrpc.c
@@ -55,7 +55,7 @@
 {
 	(void)clnt;
 
-	rpc->call->hdr.frag_hdr = htonl(LAST_FRAG | rpc->call_len);
+	rpc->call->hdr.frag_hdr = htonl(LAST_FRAG | (rpc->call_len - 4));
 	rpc->call->hdr.udp.xid = lrand48();
 	rpc->call->hdr.udp.msg_type = htonl(RPC_CALL);
 	rpc->call->rpc_vers = htonl(2);