diff --git a/src/base/base.c b/src/base/base.c
index 189ee074d..03419b3ff 100644
--- a/src/base/base.c
+++ b/src/base/base.c
@@ -1525,6 +1525,7 @@ PHP_FUNCTION(xdebug_set_time_limit)
 {
 	if (!xdebug_is_debug_connection_active()) {
 		orig_set_time_limit_func(INTERNAL_FUNCTION_PARAM_PASSTHRU);
+		return;
 	}
 
 	RETURN_FALSE;
diff --git a/tests/base/bug02439.phpt b/tests/base/bug02439.phpt
new file mode 100644
index 000000000..619419a12
--- /dev/null
+++ b/tests/base/bug02439.phpt
@@ -0,0 +1,16 @@
+--TEST--
+Test for bug #2439: Overloaded set_time_limit() always returns false, even when the limit was applied
+--INI--
+xdebug.mode=develop
+--FILE--
+<?php
+ini_set('max_execution_time', '42');
+
+var_dump(set_time_limit(0));
+var_dump(ini_get('max_execution_time'));
+?>
+--EXPECTF--
+%sbug02439.php:%d:
+bool(true)
+%sbug02439.php:%d:
+string(1) "0"