[Plugin: WP Smush.it] getting a Could not find, looks like the path is not constructed correctly

Hi, this is what happen when I try to smush.it or re-smush:

Could not find /home/sites/clients/client20/web44/web/wp-content/uploads/201105pluizenissen.jpg

The path is correct up until /home/sites/clients/client20/web44/web/wp-content/uploads but then it should say /2011/05/pluizenissen.jpg and instead it looks like it justs concatenates the folder names.

I did a bit of debugging and found out that when I did a var_dump of $original_meta = wp_get_attachment_metadata( $attachment_ID ); it looks like this and then I got really stuck:

array(7) {
  ["width"]=>
  string(3) "310"
  ["height"]=>
  string(3) "238"
  ["hwstring_small"]=>
  string(23) "height='96' width='125'"
  ["file"]=>
  string(22) "201105pluizenissen.jpg"
  ["sizes"]=>
  array(4) {
    ["thumbnail"]=>
    array(4) {
      ["file"]=>
      string(24) "pluizenissen-150x150.jpg"
      ["width"]=>
      string(3) "150"
      ["height"]=>
      string(3) "150"
      ["wp_smushit"]=>
      string(123) "Could not find <span class='code'>/home/sites/clients/client20/web44/web/wp-content/uploads/pluizenissen-150x150.jpg</span>"
    }
    ["medium"]=>
    array(4) {
...
...

My WordPress version is 3.2.1 and the Smush.it version is 1.5.0

Any help appreciated 🙂

http://wordpress.org/extend/plugins/wp-smushit/