diff --git a/epan/dissectors/packet-q931.c b/epan/dissectors/packet-q931.c
index 6f12d847f3..2995bb13d8 100644
--- a/epan/dissectors/packet-q931.c
+++ b/epan/dissectors/packet-q931.c
@@ -1200,8 +1200,8 @@ static const value_string q931_rejection_reason_vals[] = {
 	{ 0x00, NULL }
 };
 
-void
-dissect_q931_cause_ie(tvbuff_t *tvb, int offset, int len,
+static void
+dissect_q931_cause_ie_unsafe(tvbuff_t *tvb, int offset, int len,
     proto_tree *tree, int hf_cause_value, guint8 *cause_value)
 {
 	guint8 octet;
@@ -1359,6 +1359,16 @@ dissect_q931_cause_ie(tvbuff_t *tvb, int offset, int len,
 	}
 }
 
+void
+dissect_q931_cause_ie(tvbuff_t *tvb, int offset, int len,
+    proto_tree *tree, int hf_cause_value, guint8 *cause_value)
+{
+  gboolean have_valid_q931_pi_save = have_valid_q931_pi;
+  have_valid_q931_pi = FALSE;
+  dissect_q931_cause_ie_unsafe(tvb, offset, len, tree, hf_cause_value, cause_value);
+  have_valid_q931_pi =  have_valid_q931_pi_save;
+}
+
 /*
  * Dissect a Call state information element.
  */
@@ -2815,7 +2825,7 @@ dissect_q931_IEs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *root_tree,
 					break;
 
 				case CS0 | Q931_IE_CAUSE:
-					dissect_q931_cause_ie(tvb,
+					dissect_q931_cause_ie_unsafe(tvb,
 						offset + 2, info_element_len,
 						ie_tree,
 						hf_q931_cause_value, &dummy);