Index: usr.bin/truss/setup.c
===================================================================
--- usr.bin/truss/setup.c
+++ usr.bin/truss/setup.c
@@ -64,6 +64,7 @@
 static void	enter_syscall(struct trussinfo *, struct threadinfo *,
 		    struct ptrace_lwpinfo *);
 static void	new_proc(struct trussinfo *, pid_t, lwpid_t);
+static void	find_thread(struct trussinfo *info, pid_t pid, lwpid_t lwpid);
 
 /*
  * setup_and_wait() is called to start a process.  All it really does
@@ -223,8 +224,10 @@
 		t = new_thread(p, lwps[i]);
 		if (ptrace(PT_LWPINFO, lwps[i], (caddr_t)&pl, sizeof(pl)) == -1)
 			err(1, "ptrace(PT_LWPINFO)");
-		if (pl.pl_flags & PL_FLAG_SCE)
+		if (pl.pl_flags & PL_FLAG_SCE) {
+			find_thread(info, p->pid, pl.pl_lwpid);
 			enter_syscall(info, t, &pl);
+		}
 	}
 	free(lwps);
 }