diff --git a/lib/libifconfig/libifconfig_sfp.c b/lib/libifconfig/libifconfig_sfp.c
--- a/lib/libifconfig/libifconfig_sfp.c
+++ b/lib/libifconfig/libifconfig_sfp.c
@@ -181,6 +181,7 @@
 	if (code & SFF_8636_EXT_COMPLIANCE) {
 		read_i2c(ii, SFF_8436_BASE, SFF_8436_OPTIONS_START, 1,
 		    &sfp->sfp_eth_ext);
+		sfp->sfp_eth_1040g = code;
 	} else {
 		/* Check 10/40G Ethernet class only */
 		sfp->sfp_eth_1040g =