Mail Archive feature retrieve inline images as just one image.png

The mail archive feature is not working properly for inline images.

Steps to reproduce.

1) Install Confluence 5.4.1 and activate the Mail archive feature
2) Setup an space to receive the email archive
3) Create a new email and attach 2 or more inline images in this email.
4) Send the email to confluence and go to the space mail tab and verify the new email
5) Open the email and you'll see the multiple images as image.png
6) If you click on any of these image.png, just the first image will be loaded, not the others, although the size of the files are different.