--- /dev/null
+--TEST--
+message body to callback
+--SKIPIF--
+<?php
+include "skipif.inc";
+?>
+--FILE--
+<?php
+echo "Test\n";
+
+$file = new http\Message\Body(fopen(__FILE__,"r"));
+$s = "";
+$file->toCallback(
+ function($body, $string) use (&$s) { $s.=$string; }
+);
+var_dump($s === (string) $file);
+
+?>
+DONE
+--EXPECT--
+Test
+bool(true)
+DONE