diff --git a/WebLoader/Compiler.php b/WebLoader/Compiler.php
index 370995e..1dc2bef 100644
--- a/WebLoader/Compiler.php
+++ b/WebLoader/Compiler.php
@@ -216,7 +216,7 @@ protected function generateFiles(array $files, $ifModified, array $watchFiles =
 
 		return (object) array(
 			'file' => $name,
-			'lastModified' => $lastModified,
+			'lastModified' => filemtime($path),
 			'sourceFiles' => $files,
 		);
 	}
diff --git a/tests/CompilerTest.php b/tests/CompilerTest.php
index b0fd0d1..e8ef8b0 100644
--- a/tests/CompilerTest.php
+++ b/tests/CompilerTest.php
@@ -107,7 +107,7 @@ public function testGeneratingAndFilters()
 
 		$files = $this->object->generate();
 
-		$this->assertTrue(is_numeric($files[0]->lastModified), 'Generate does not provide last modified timestamp correctly.');
+		$this->assertTrue(is_numeric($files[0]->lastModified) && $files[0]->lastModified > 0, 'Generate does not provide last modified timestamp correctly.');
 
 		$content = file_get_contents($this->object->getOutputDir() . '/' . $files[0]->file);