diff --git a/src/grib_dumper_class_filter.c b/src/grib_dumper_class_filter.c
index 762359133..01819831f 100644
--- a/src/grib_dumper_class_filter.c
+++ b/src/grib_dumper_class_filter.c
@@ -434,7 +434,7 @@ static void dump_string(grib_dumper* d,grib_accessor* a,const char* comment)
     err = grib_unpack_string(a,value,&size);
     p=value;
     r=get_key_rank(h,self->keys,a->name);
-    if (grib_is_missing_string(a,value,size))
+    if (grib_is_missing_string(a,(unsigned char *)value,size))
         return;
 
     while(*p) { if(!isprint(*p)) *p = '.'; p++; }
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 6390fa971..527941f75 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -56,6 +56,7 @@ list( APPEND tests2
     bufr_ls
     bufr_change_edition
     ecc-197
+    ecc-286
     gts_get
     gts_ls
     gts_compare
diff --git a/tests/bufr_dump.sh b/tests/bufr_dump.sh
index defeac83d..b0425bb31 100755
--- a/tests/bufr_dump.sh
+++ b/tests/bufr_dump.sh
@@ -30,7 +30,7 @@ REDIRECT=/dev/null
 
 for file in ${bufr_files}
 do
-  ${tools_dir}bufr_dump -O ${data_dir}/bufr/$file
+  ${tools_dir}bufr_dump -O ${data_dir}/bufr/$file >/dev/null
 done
 
 #==============================================
diff --git a/tests/ecc-286.sh b/tests/ecc-286.sh
new file mode 100755
index 000000000..391d8998c
--- /dev/null
+++ b/tests/ecc-286.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+# Copyright 2005-2016 ECMWF.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+# 
+# In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
+# virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
+#
+
+. ./include.sh
+
+# ---------------------------------------------------------
+# This is the test for the JIRA issue ECC-286.
+# It tests setting a key which starts with a digit
+# ---------------------------------------------------------
+cd ${data_dir}/bufr
+label="ecc_286_test"
+
+tempRules=temp.${label}.filter
+tempOut=temp.${label}.out
+tempRef=temp.${label}.ref
+BufrFile=syno_1.bufr
+
+cat > $tempRules <<EOF
+ set unpack=1;
+ print "[3HourPressureChange]";
+ set 3HourPressureChange=21;
+ print "[3HourPressureChange]";
+EOF
+
+${tools_dir}bufr_filter $tempRules $BufrFile > $tempOut
+
+cat > $tempRef <<EOF
+20
+21
+EOF
+
+diff $tempRef $tempOut
+
+rm -rf $tempOut $tempRef $tempRules