I downloaded your file and was just looking at each file with Notepad.
WTF are all of these hostile comments your program for?
Is that hostility toward the SMS messages or us?

It makes me hesitant to install it seeing them:

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#!/bin/sh
# mpf / matt@utternerd.org (aka mrplastik)
# http://utternerd.org for further details.
# v0.0.2 Clear ALL SMS messages and rebuild valid null db.

# I hate you, all of you - Die goddamnit.
/Applications/CASMS.app/sqlite3 -batch /var/mobile/Library/SMS/sms.db < /Applications/CASMS.app/cleanup.sql

# Enforce file perms - shouldn't be needed.
chown mobile:mobile /var/mobile/Library/SMS/sms.db
chmod 644 /var/mobile/Library/SMS/sms.db

# Refreshes message count, but is not necessary.
killall SpringBoard