diff --git a/image.php b/image.php
index e11b73f..87717e7 100644
--- a/image.php
+++ b/image.php
@@ -62,7 +62,7 @@ $gotova_slika = $imagine->create($okvir_size, $color);
 $gotova_slika->paste($okvir_image, new Imagine\Image\Point(0,0));
 
 $imeslike = "$okvir_id" . "$slika";
-$etag = mhash(MHASH_ADLER32, $imeslike);
+$etag = bin2hex(mhash(MHASH_ADLER32, $imeslike));
 header("Etag: $etag"); 
 
 $seconds_to_cache = 86400;