Issue:
iPhone 4 freezes after exiting the Bluefire reader requiring a hard reset of the device to recover. Issue is reproducible 100%
Steps to Reproduce:
1. Launch Application BlueFire
2. Login to account authorizing device to read adobe content
3. Once you have authorized device press the Home button on the iphone to exit the application.
***Observe the iphone 4 is now frozen and requires a hard reset to recover from this.

I am at work or I would re-install the software and try and get you a log from the device from Organizer in xcode but don't have time. Hopefully this information helps. I will reproduce and capture a log if you are still unable to reproduce let me know. I develop iphone apps so I am familiar with the development environment.
Below are my software and hardware information to aid in reproducing this issue:
iPhone 4.2.1 ( 8C148 )
Firmware: 02.10.04
Carrier: AT&T 9.0
Model: MC610LL
Cydia Packages Installed:
APR, APT 0.7, APT 0.8 strict(lib),Base Structure, BigBoss's source, Bourne-Again Shell, bzip2, Core Utilities (/bin), Cydia Community Sources, Cydia Installer, Darwin Tools, Debian Packager, Dev-Team, Diff Utilities, diskdev-cmds, Find Utilities, GNU Privacy Guard, grep, gzip, libxml2 Library, LZMA utils, Mobile Substrate, ModMyi.com, My3G, New Curses, OpenSSH, OpenSSL, PAM, PAM Modules, pcre, PreferenceLoader, Profile Directory, readline, Saurik's Source, sed, shell-cmds, SQLite 3.x Library, system-cmds, Tape Archive, TetherMe, ThetherMe APN Editing, TetherMe Preferences, UIKit Tools, ZodTTD's Sources.
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Cydia Packages beyond the default that I installed that may be to blame:
OpenSSH, TetherMe, My3g ---> I would first try installing those and then testing to see if you see the issues. Both tetherme and my3g however are paid apps, so perhaps start with just OpenSSH as an additional install to reproduce.
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