Import Dotclear text file to WordPress 3.5

Hello,

I exported a blog-backup.txt file from my Dotclear 1.2.6 blog and I would like to import it to WordPress 3.5, but in the Tools > Import section, I can’t seem to do it with a text file. Besides, the plain “Dotclear” import tool in WP 3.5 does not work for me.

Thank you if you can help.