diff --git a/wiretap/ngsniffer.c b/wiretap/ngsniffer.c
index 60491592ff..40bd388e5d 100644
--- a/wiretap/ngsniffer.c
+++ b/wiretap/ngsniffer.c
@@ -1,6 +1,6 @@
 /* ngsniffer.c
  *
- * $Id: ngsniffer.c,v 1.107 2003/01/11 05:54:52 guy Exp $
+ * $Id: ngsniffer.c,v 1.108 2003/01/14 19:52:47 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -509,24 +509,44 @@ int ngsniffer_open(wtap *wth, int *err)
 	 *
 	 * XXX - in some version 1.16 internetwork analyzer files
 	 * generated by the Windows Sniffer when saving Windows
-	 * Sniffer files as DOS Sniffer files, the first "rsvd" word
-	 * is 1 for PRI ISDN files, 2 for BRI ISDN files, and 0 for
-	 * non-ISDN files; is that something the DOS Sniffer understands?
+	 * Sniffer files as DOS Sniffer files, there's no REC_HEADER2
+	 * record, but the first "rsvd" word is 1 for PRI ISDN files, 2
+	 * for BRI ISDN files, and 0 for non-ISDN files; is that something
+	 * the DOS Sniffer understands?
 	 */
 	maj_vers = pletohs(&version.maj_vers);
 	if (process_header_records(wth, err, maj_vers) < 0)
 		return -1;
-	if (wth->file_encap == WTAP_ENCAP_PER_PACKET && maj_vers == 1) {
+	if (wth->file_encap == WTAP_ENCAP_PER_PACKET) {
 		/*
 		 * Well, we haven't determined the internetwork analyzer
-		 * subtype yet, and this is a version 1 capture; look
-		 * at the first "rsvd" word.
+		 * subtype yet...
 		 */
-		switch (pletohs(&version.rsvd[0])) {
+		switch (maj_vers) {
 
 		case 1:
-		case 2:
-			wth->file_encap = WTAP_ENCAP_ISDN;
+			/*
+			 * ... and this is a version 1 capture; look
+			 * at the first "rsvd" word.
+			 */
+			switch (pletohs(&version.rsvd[0])) {
+
+			case 1:
+			case 2:
+				wth->file_encap = WTAP_ENCAP_ISDN;
+				break;
+			}
+			break;
+
+		case 3:
+			/*
+			 * ...and this is a version 3 capture; we've
+			 * seen nothing in those that obviously
+			 * indicates the capture type, but the only
+			 * one we've seen is a Frame Relay capture,
+			 * so mark it as Frame Relay for now.
+			 */
+			wth->file_encap = WTAP_ENCAP_FRELAY;
 			break;
 		}
 	}