bpetersxxx does not have my first Calypso. The one he has was procured locally in his area by hisownself. Both of mine, the platinum machine purchased on 10/14/2006, and the white bought on 8/2/2007, are in my possession. I have not disassembled the platinum for a look at the tub, but having observed it from outside with the panels removed, there appears to be no sludge. The white also did NOT have a build-up of sludge per se. The residue in the tub was light and flaky. The layer on outside of the basket was of a more heavy, sticky variety (probably softener-related), but washed off easily with water and a nylon scrub brush.
I am running a Whitest Whites load in the white machine at this moment. Hot wash, cold rinse, heavy soil, soak option. Wisk HE liquid + oxy-booster powder. No LCB or softener.