diff --git a/src/parse_aprs.c b/src/parse_aprs.c
index 1ca9c93..9c9a841 100644
--- a/src/parse_aprs.c
+++ b/src/parse_aprs.c
@@ -509,7 +509,7 @@ static int parse_aprs_nmea(struct pbuf_t *pb, const char *body, const char *body
 	}
 	
 	if (!latp || !lngp) {
-		hlog(LOG_DEBUG, "Unknown NMEA: '%.11s' %.*s", pb->data, (int)(body_end - body), body);
+		hlog_packet(LOG_DEBUG, pb->data, pb->packet_len-2, "Unknown NMEA: ");
 		return 0; /* Well..  Not NMEA frame */
 	}
 
diff --git a/tests/t/31parser-nmea.t b/tests/t/31parser-nmea.t
index df0c335..bd53deb 100644
--- a/tests/t/31parser-nmea.t
+++ b/tests/t/31parser-nmea.t
@@ -6,7 +6,7 @@
 #
 
 use Test;
-BEGIN { plan tests => 11 };
+BEGIN { plan tests => 12 };
 use runproduct;
 use istest;
 use Ham::APRS::IS;
@@ -55,6 +55,13 @@ istest::should_drop(\&ok, $i_tx, $i_rx,
         $tx, # should drop
         $dummy, 1, 1); # will pass (helper packet)
 
+# 11: should drop, invalid char in coordinates
+$tx = "OH4XYZ>GPSMW:\$GPRMO,182051.\xf000,A,6039.8655,N,01708.3799,E,20.07,243.41,070313,,,A*5A";
+$dummy = "OH5XYZ>GPSMV:\$GPRMC,212052,A,4609.1157,N,12258.8145,W,0.168,13.4,130909,17.9,E*6B";
+istest::should_drop(\&ok, $i_tx, $i_rx,
+        $tx, # should drop
+        $dummy, 1, 1); # will pass (helper packet)
+
 # stop
 
 ok($p->stop(), 1, "Failed to stop product");