diff --git a/config.mk b/config.mk
index 2850bee..c39d47c 100644
--- a/config.mk
+++ b/config.mk
@@ -1,5 +1,5 @@
 #use this to compile with USB support
 #CFLAGS?=-DISI_USB
 PREFIX?=/usr
-PLUGINDIR?=lib/wireshark/libwireshark1/plugins
+PLUGINDIR?=lib/wireshark/libwireshark2/plugins
 WIRESHARKDIR?=/usr/include/wireshark
diff --git a/src/packet-isi.c b/src/packet-isi.c
index a92800b..0868f83 100644
--- a/src/packet-isi.c
+++ b/src/packet-isi.c
@@ -520,9 +520,9 @@ static void dissect_isi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree) {
 		dst = tvb_get_guint8(tvb, 0);
 		src = tvb_get_guint8(tvb, 1);
 
-		if(tvb->length - 8 < length) {
-			expert_add_info_format(pinfo, item, PI_PROTOCOL, PI_WARN, "Broken Length (%d > %d)", length, tvb->length-8);
-			length = tvb->length - 8;
+		if(tvb_length(tvb) - 8 < length) {
+			expert_add_info_format(pinfo, item, PI_PROTOCOL, PI_WARN, "Broken Length (%d > %d)", length, tvb_length(tvb)-8);
+			length = tvb_length(tvb) - 8;
 		}
 
 		col_set_str(pinfo->cinfo, COL_DEF_SRC, val_to_str_const(src, hf_isi_device, "Unknown"));