diff --git a/helper.c b/helper.c
index 84c898d2f1..76b3bcd85c 100644
--- a/helper.c
+++ b/helper.c
@@ -217,6 +217,35 @@ int php_git2_cb_init(php_git2_cb_t **out, zend_fcall_info *fci, zend_fcall_info_
 	cb->payload = payload;
 	cb->fci = fci;
 	cb->fcc = fcc;
+	cb->is_copy = 0;
+	GIT2_TSRMLS_SET2(cb, TSRMLS_C);
+
+	*out = cb;
+	return 0;
+}
+
+int php_git2_cb_init_copy(php_git2_cb_t **out, zend_fcall_info *fci, zend_fcall_info_cache *fcc, void *payload TSRMLS_DC)
+{
+	php_git2_cb_t *cb;
+
+	cb = (struct php_git2_cb_t*)emalloc(sizeof(php_git2_cb_t));
+	if (cb == NULL) {
+		return 1;
+	}
+
+	cb->payload = payload;
+	// use fci->size instead of sizeof?
+	cb->fci = (zend_fcall_info*)emalloc(sizeof(zend_fcall_info));
+	cb->fcc = (zend_fcall_info_cache*)emalloc(sizeof(zend_fcall_info_cache));
+	memcpy(cb->fci, fci, sizeof(zend_fcall_info));
+	memcpy(cb->fcc, fcc, sizeof(zend_fcall_info_cache));
+	Z_ADDREF_P(cb->fci->function_name);
+#if PHP_VERSION_ID >= 50300
+	if (cb->fci->object_ptr) {
+		Z_ADDREF_P(cb->fci->object_ptr);
+	}
+#endif
+	cb->is_copy = 1;
 	GIT2_TSRMLS_SET2(cb, TSRMLS_C);
 
 	*out = cb;
@@ -225,6 +254,14 @@ int php_git2_cb_init(php_git2_cb_t **out, zend_fcall_info *fci, zend_fcall_info_
 
 void php_git2_cb_free(php_git2_cb_t *target)
 {
+	if (target->is_copy) {
+		Z_DELREF_P(target->fci->function_name);
+#if PHP_VERSION_ID >= 50300
+		if (target->fci->object_ptr) {
+			Z_DELREF_P(target->fci->object_ptr);
+		}
+#endif
+	}
 	efree(target);
 }
 
diff --git a/helper.h b/helper.h
index 424f1c3f89..3cf5e942d5 100644
--- a/helper.h
+++ b/helper.h
@@ -49,6 +49,8 @@ int php_git2_call_function_v(
 
 int php_git2_cb_init(php_git2_cb_t **out, zend_fcall_info *fci, zend_fcall_info_cache *fcc, void *payload TSRMLS_DC);
 
+int php_git2_cb_init_copy(php_git2_cb_t **out, zend_fcall_info *fci, zend_fcall_info_cache *fcc, void *payload TSRMLS_DC);
+
 void php_git2_cb_free(php_git2_cb_t *target);
 
 void php_git2_array_to_strarray(git_strarray *out, zval *array TSRMLS_DC);
@@ -100,4 +102,4 @@ void php_git2_fcall_info_wrapper(zval *target, zend_fcall_info **out_fci, zend_f
 
 void php_git2_fcall_info_wrapper2(zval *target, zend_fcall_info *fci, zend_fcall_info_cache *fcc TSRMLS_DC);
 
-#endif
\ No newline at end of file
+#endif
diff --git a/php_git2.h b/php_git2.h
index 4c5493a976..43b9c2850b 100644
--- a/php_git2.h
+++ b/php_git2.h
@@ -203,6 +203,7 @@ typedef struct php_git2_cb_t {
 	zval *payload;
 	zend_fcall_info *fci;
 	zend_fcall_info_cache *fcc;
+	int is_copy;
 	GIT2_TSRMLS_DECL
 } php_git2_cb_t;
 
diff --git a/transport.c b/transport.c
index 4904517ab5..4860723f60 100644
--- a/transport.c
+++ b/transport.c
@@ -73,11 +73,10 @@ PHP_FUNCTION(git_transport_register)
 		return;
 	}
 
-	if (php_git2_cb_init(&cb, &fci, &fcc, param TSRMLS_CC)) {
+	if (php_git2_cb_init_copy(&cb, &fci, &fcc, param TSRMLS_CC)) {
 		RETURN_FALSE;
 	}
 	result = git_transport_register(prefix, priority, php_git2_transport_cb, cb);
-	php_git2_cb_free(cb);
 	RETURN_LONG(result);
 }
 /* }}} */