diff --git a/base-nova/src/base/ipc/ipc.cc b/base-nova/src/base/ipc/ipc.cc
index 6e9031661..458d4a139 100644
--- a/base-nova/src/base/ipc/ipc.cc
+++ b/base-nova/src/base/ipc/ipc.cc
@@ -57,7 +57,7 @@ static void copy_utcb_to_msgbuf(Nova::Utcb *utcb, Msgbuf_base *rcv_msg)
 /**
  * Copy message payload to UTCB message registers
  */
-static void copy_msgbuf_to_utcb(Nova::Utcb *utcb, Msgbuf_base *snd_msg,
+static bool copy_msgbuf_to_utcb(Nova::Utcb *utcb, Msgbuf_base *snd_msg,
                                 unsigned num_msg_words, mword_t local_name)
 {
 	/* look up address and size of message payload */
@@ -87,11 +87,14 @@ static void copy_msgbuf_to_utcb(Nova::Utcb *utcb, Msgbuf_base *snd_msg,
 		int pt_sel = snd_msg->snd_pt_sel(i);
 		if (pt_sel < 0) continue;
 
-		utcb->append_item(Nova::Obj_crd(pt_sel, 0), i);
+		if (!utcb->append_item(Nova::Obj_crd(pt_sel, 0), i))
+			return false;
 	}
 
 	/* we have consumed portal capability selectors, reset message buffer */
 	snd_msg->snd_reset();
+
+	return true;
 }
 
 
@@ -133,8 +136,11 @@ void Ipc_client::_call()
 {
 	Nova::Utcb *utcb = (Nova::Utcb *)Thread_base::myself()->utcb();
 
-	copy_msgbuf_to_utcb(utcb, _snd_msg, _write_offset/sizeof(mword_t),
-	                    Ipc_ostream::_dst.local_name());
+	if (!copy_msgbuf_to_utcb(utcb, _snd_msg, _write_offset/sizeof(mword_t),
+	                         Ipc_ostream::_dst.local_name())) {
+		PERR("could not setup IPC");
+		return;
+	}
 	_rcv_msg->rcv_prepare_pt_sel_window(utcb);
 
 	/* establish the mapping via a portal traversal */
diff --git a/base-nova/src/base/ipc/pager.cc b/base-nova/src/base/ipc/pager.cc
index a39026083..0e6d4fa9b 100644
--- a/base-nova/src/base/ipc/pager.cc
+++ b/base-nova/src/base/ipc/pager.cc
@@ -57,7 +57,9 @@ void Ipc_pager::set_reply_mapping(Mapping m)
 {
 	Nova::Utcb *utcb = (Nova::Utcb *)Thread_base::myself()->utcb();
 	utcb->set_msg_word(0);
-	utcb->append_item(m.mem_crd(), m.dst_addr());
+	bool res = utcb->append_item(m.mem_crd(), m.dst_addr());
+	/* one item ever fits on the UTCB */
+	(void)res;
 }
 
 
diff --git a/base-nova/src/base/pager/pager.cc b/base-nova/src/base/pager/pager.cc
index def0b0cda..92e3e67b4 100644
--- a/base-nova/src/base/pager/pager.cc
+++ b/base-nova/src/base/pager/pager.cc
@@ -79,8 +79,11 @@ void Pager_object::_invoke_handler()
 	utcb->mtd = 0;
 	utcb->set_msg_word(0);
 
-	if (event == PT_SEL_STARTUP || event == PT_SEL_PAGE_FAULT)
-		utcb->append_item(Obj_crd(obj->exc_pt_sel() + event, 0), 0);
+	if (event == PT_SEL_STARTUP || event == PT_SEL_PAGE_FAULT) {
+		bool res = utcb->append_item(Obj_crd(obj->exc_pt_sel() + event, 0), 0);
+ 		/* one item ever fits on the UTCB */
+		(void)res;
+	}
 
 	reply(Thread_base::myself()->stack_top());
 }