diff --git a/Zend/zend_execute.h b/Zend/zend_execute.h
index 78b79431a9d80..d0adabab066f0 100644
--- a/Zend/zend_execute.h
+++ b/Zend/zend_execute.h
@@ -156,6 +156,8 @@ static zend_always_inline int i_zend_is_true(zval *op)
 }
 
 ZEND_API int zval_update_constant(zval **pp, void *arg TSRMLS_DC);
+ZEND_API int zval_update_constant_inline_change(zval **pp, void *arg TSRMLS_DC);
+ZEND_API int zval_update_constant_no_inline_change(zval **pp, void *arg TSRMLS_DC);
 ZEND_API int zval_update_constant_ex(zval **pp, void *arg, zend_class_entry *scope TSRMLS_DC);
 
 /* dedicated Zend executor functions - do not use! */
diff --git a/Zend/zend_execute_API.c b/Zend/zend_execute_API.c
index a0dcb48e64fc4..91e1b6aec8d5f 100644
--- a/Zend/zend_execute_API.c
+++ b/Zend/zend_execute_API.c
@@ -684,13 +684,25 @@ ZEND_API int zval_update_constant_ex(zval **pp, void *arg, zend_class_entry *sco
 			}
 			zval_dtor(&const_value);
 		}
-		zend_hash_apply_with_argument(Z_ARRVAL_P(p), (apply_func_arg_t) zval_update_constant, (void *) 1 TSRMLS_CC);
+		zend_hash_apply_with_argument(Z_ARRVAL_P(p), (apply_func_arg_t) zval_update_constant_inline_change, (void *) scope TSRMLS_CC);
 		zend_hash_internal_pointer_reset(Z_ARRVAL_P(p));
 	}
 	return 0;
 }
 /* }}} */
 
+ZEND_API int zval_update_constant_inline_change(zval **pp, void *scope TSRMLS_DC) /* {{{ */
+{
+	return zval_update_constant_ex(pp, (void*)1, scope TSRMLS_CC);
+}
+/* }}} */
+
+ZEND_API int zval_update_constant_no_inline_change(zval **pp, void *scope TSRMLS_DC) /* {{{ */
+{
+	return zval_update_constant_ex(pp, (void*)0, scope TSRMLS_CC);
+}
+/* }}} */
+
 ZEND_API int zval_update_constant(zval **pp, void *arg TSRMLS_DC) /* {{{ */
 {
 	return zval_update_constant_ex(pp, arg, NULL TSRMLS_CC);
diff --git a/ext/reflection/tests/bug51905.phpt b/ext/reflection/tests/bug51905.phpt
new file mode 100644
index 0000000000000..8969924e45f36
--- /dev/null
+++ b/ext/reflection/tests/bug51905.phpt
@@ -0,0 +1,28 @@
+--TEST--
+Bug #51905 (ReflectionParameter fails if default value is an array with an access to self::)
+--FILE--
+<?php
+
+class Bar {
+	const Y = 20;
+}
+
+class Foo extends Bar {
+	const X = 12;
+	public function x($x = 1, $y = array(self::X), $z = parent::Y) {}
+}
+
+$clazz = new ReflectionClass('Foo');
+$method = $clazz->getMethod('x');
+foreach ($method->getParameters() as $param) {
+    if ( $param->isDefaultValueAvailable())
+        echo '$', $param->getName(), ' : ', var_export($param->getDefaultValue(), 1), "\n";
+}
+
+?>
+--EXPECT--
+$x : 1
+$y : array (
+  0 => 12,
+)
+$z : 20