The fact is that both of my drives are more or less corrupted. So now I will try to reformat a partition and see what happens with huge files. Also, I should mention that before that serious fs corruption I had several files wrongly copied from one disk to another. I copied about 5 GB of photos and some of them appeared corrupted. I'll look and see if I still can find some missed ones as I had them replaced one by one with the originals and they were successfully corrected. http://jozita.lt/Problem.zip
here it is. Three pairs of photos corrupted during PATA->SATA copy operation.
Here are my PATA->fresh ext3 partition on SATA:
17050436099fb9a05ad03ae2cce1a607 debian-update-3.1r4-i386-1.iso - the source
... and the copies (filenames changed on purpose
Lastly, because of such differences I decided to check them once more. Every file had a different md5sum! Even in the fresh partition it gives different md5sum.