diff --git epan/dissectors/packet-tcp.c epan/dissectors/packet-tcp.c
index 58bbb5a..ad0648d 100644
--- epan/dissectors/packet-tcp.c
+++ epan/dissectors/packet-tcp.c
@@ -1940,6 +1940,19 @@ again:
             fragment_add(tvb, deseg_offset, pinfo, msp->first_frame,
                          tcp_fragment_table, 0, nxtseq - deseg_seq,
                          LT_SEQ(nxtseq, msp->nxtpdu));
+
+			/* check if we've already have PDU which overlaps with this one */
+			{
+				struct tcp_multisegment_pdu *msp2 = se_tree_lookup32_le(tcpd->fwd->multisegment_pdus, msp->nxtpdu);
+
+				/* msp2 should never be NULL */
+				if (msp2 != NULL && msp2 != msp) {
+					/* 
+					 * XXX, what can we do here? 
+					 */
+					g_warning("XXX, msp != msp2 (%u...%u %u)\n", msp->seq, msp->nxtpdu, msp2->seq);
+				}
+			}
         }
     }