Yup, IFS
It even works perfectly with Windows Vista, but you've to specify "Run as Administrator..." to start the installation unlike many other programs.
grey_moon: If I understand it well (jeez.. it's past midnight ^^') you're truecrypt volume is ext3 formatted and you mount it Windows using IFS drivers?
I've one that was NTFS formatted (created on windows like 2 years ago) and have to mount it in Linux with the --filesystem ntfs-3g option.
I experience this a quite slower than using it with windows.
That's why the new truecrypt volume is formatted as FAT32, which is way faster on both OSes.
The external HD itself is {100MB FAT32}{159,9GB EXT3} That FAT32 partition is for having the IFS installer should I need to connect the HD to someone else's PC.