sfill crashes occassionally during wipe

[Andreas Heinlein]

Binary package hint: secure-delete

sfill sometimes crashes during the overwriting process and exits with
"glibc detected *** /usr/bin/sfill free(): invalid next size(fast) 0x12345678

I have not yet found a way to reproduce this, but from what I've found using Google, this looks much like a programming error that occurs only in combination with certain versions of glibc.

sfill was always called as 'sfill -l -l /path/to/mountpoint'.

Ubuntu version: 8.04, secure-delete version 3.1-4