During a fresh instalation it was not possible to choose de ext4 file format. The only journal file system that appears was the xfs. I tested two times with the same results.
The image that I used was the "debian-testing-i386-netinst.iso 2015-03-02 05:48 304M" booted from a usb pen drive.
Best regards --
Com os melhores cumprimentos,
Miguel Mourão