diff --git a/Zend/tests/bug72581.phpt b/Zend/tests/bug72581.phpt
new file mode 100644
index 00000000000..775f6e360db
--- /dev/null
+++ b/Zend/tests/bug72581.phpt
@@ -0,0 +1,17 @@
+--TEST--
+Bug #72581 (previous property undefined in Exception after deserialization)
+--FILE--
+<?php
+
+$e = new Exception('aaa', 200);
+
+$a = serialize($e);
+
+$b = unserialize($a);
+
+var_dump($b->__toString());
+?>
+--EXPECTF--
+string(%s) "Exception: aaa in %sbug72581.php:%d
+Stack trace:
+#0 {main}"
diff --git a/Zend/zend_exceptions.c b/Zend/zend_exceptions.c
index f73dde1a974..7fd55a4fc81 100644
--- a/Zend/zend_exceptions.c
+++ b/Zend/zend_exceptions.c
@@ -303,9 +303,8 @@ ZEND_METHOD(exception, __construct)
 /* {{{ proto Exception::__wakeup()
    Exception unserialize checks */
 #define CHECK_EXC_TYPE(id, type) \
-	ZVAL_UNDEF(&value); \
 	pvalue = zend_read_property_ex(i_get_exception_base(object), (object), CG(known_strings)[id], 1, &value); \
-	if(Z_TYPE_P(pvalue) != IS_UNDEF && Z_TYPE_P(pvalue) != type) { \
+	if (Z_TYPE_P(pvalue) != IS_NULL && Z_TYPE_P(pvalue) != type) { \
 		zval tmp; \
 		ZVAL_STR_COPY(&tmp, CG(known_strings)[id]); \
 		Z_OBJ_HANDLER_P(object, unset_property)(object, &tmp, NULL); \