I’ve been finding lots of .deb packages that are compiled for 32-bit OS’s that don’t have 64-bit versions available. While this may not be the most elegant solution, it’s been allowing me to install things like Adobe AIR and DiffMerge, which don’t have 64-bit .deb packages:

First, navigate to the location of the .deb folder.

Once there do the following:

1. Make a tmp directory to hold the package
   $ mkdir tmp

2. Extract the .deb package into the tmp directory
   $ dpkg-deb -x package.deb tmp

3. Extract the control files
   $ dpkg-deb --control package.deb tmp/DEBIAN

4. Change the Architecture parameter from “i386″ to “all”
   $ sed -i "s/i386/all/" tmp/DEBIAN/control

5. Repackage the .deb into your new 64-bit version
   $ dpkg -b tmp package_64.deb

6. Install the new 64-bit .deb version :)
   $ sudo dpkg -i package_64.deb

I’m not going to say this will work for EVERY package b/c you are essentially faking out the installer to think your system is supported. You may run into some application errors due to this, however, I have experienced none as of yet.

Adapted from jamesward.com