diff --git a/conformance/failure_list_php.txt b/conformance/failure_list_php.txt
index 0d2341127ec31..8bd8a99ea4e70 100644
--- a/conformance/failure_list_php.txt
+++ b/conformance/failure_list_php.txt
@@ -13,6 +13,8 @@ Required.Proto3.JsonInput.FloatFieldTooSmall
 Required.Proto3.JsonInput.DoubleFieldTooSmall
 Required.Proto3.JsonInput.Int32FieldNotInteger
 Required.Proto3.JsonInput.Int64FieldNotInteger
+Required.Proto3.JsonInput.RepeatedFieldWrongElementTypeExpectingStringsGotInt
+Required.Proto3.JsonInput.StringFieldNotAString
 Required.Proto3.JsonInput.Uint32FieldNotInteger
 Required.Proto3.JsonInput.Uint64FieldNotInteger
 Required.Proto3.JsonInput.Int32FieldLeadingSpace
diff --git a/php/src/Google/Protobuf/Internal/Message.php b/php/src/Google/Protobuf/Internal/Message.php
index d304a12b474f3..2c41c7aa75f90 100644
--- a/php/src/Google/Protobuf/Internal/Message.php
+++ b/php/src/Google/Protobuf/Internal/Message.php
@@ -832,6 +832,9 @@ private function convertJsonValueToProtoValue(
                 if (is_null($value)) {
                     return $this->defaultValue($field);
                 }
+                if (is_numeric($value)) {
+                    return strval($value);
+                }
                 if (!is_string($value)) {
                     throw new GPBDecodeException(
                         "String field only accepts string value");
diff --git a/php/tests/encode_decode_test.php b/php/tests/encode_decode_test.php
index 57b1bf1f5fe36..1325db2cf8907 100644
--- a/php/tests/encode_decode_test.php
+++ b/php/tests/encode_decode_test.php
@@ -1148,4 +1148,14 @@ public function testJsonDecodeMapWithDefaultValueKey()
                           $m->serializeToJsonString());
     }
 
+    public function testJsonDecodeNumericStringMapKey()
+    {
+        $m = new TestMessage();
+        $m->getMapStringString()["1"] = "1";
+        $data = $m->serializeToJsonString();
+        $this->assertSame("{\"mapStringString\":{\"1\":\"1\"}}", $data);
+        $n = new TestMessage();
+        $n->mergeFromJsonString($data);
+    }
+
 }
diff --git a/tests.sh b/tests.sh
index 2f453bdc8002a..618b6864fd2f1 100755
--- a/tests.sh
+++ b/tests.sh
@@ -482,7 +482,7 @@ build_php5.6_mac() {
   export PATH="$PHP_FOLDER/bin:$PATH"
 
   # Install phpunit
-  curl https://phar.phpunit.de/phpunit-5.6.10.phar -L -o phpunit.phar
+  curl https://phar.phpunit.de/phpunit-5.6.8.phar -L -o phpunit.phar
   chmod +x phpunit.phar
   sudo mv phpunit.phar /usr/local/bin/phpunit