Nothing to do for current sid:

# debconf-get-selections | grep dash
# Use dash as the default system shell (/bin/sh)?
dash    dash/sh boolean true

Regarding dash in testing/squeeze:

Checking dash
trying to update dash from 0.5.5.1-2 to 0.5.5.1-2.3 (candidate is 6 days old) 
dash is not yet built on kfreebsd-i386: 0.5.5.1-2.2 vs 0.5.5.1-2.3 (missing 1 
binary: dash)

  -- http://release.debian.org/migration/testing.pl?package=dash

So I'll close this bugreport for now as we've nothing to do in our toolchain. 
If we notice any bugs in any tools/scripts/... we should file separate 
bugreports anyway.

thx && regards,
-mika-