How to recover a Ruined filesystem of one partition with fsck

[rajibando]

I ruined a filesystem where my Debian 6.0.3 resided in an ext3 filesystem and I boot using multiboot option on grub.cfg. While automatically running fsck Debian gave me an whether to run fsck on a mounted partition. I accidentally pressed "enter" and now can't access the filesystem.
How to recover the filesystem? Knoppix has gparted but gpart was not installed. So I installed and ran gpart but it doesn't help.
How can I recover the data there?
The snapshot will illustrate.
238

[rajibando]

Oof! Thank God! Ran

fsck -a /dev/sda6
in superuser mode, and was saved. gparted didn't work!