crypted filesystems

Hi, I noticed the possibility to create crypted file system and wanted to give it a try on one of my data partition. I checked crypt checkbox for one of ext3 partitions, entered password two times and noticed that crypting information was even written correctly into XML-file, but Ifter installing I can't find any visible sign of crypted file system. Nothing different in fstab/mount. Do I search signs from wrong places or crypting really doesn't have to work this time? -- Peeter