How to make a non-compatible HP printer work with an Apple Airport Express? (Mac OS X)

I own an HP 3745 printer (same as 3740), which I was able to use remotely with my Airport Express quite easily on my laptop running Windows and Linux (in both cases, create an IP printing port and use the normal driver).

However when I switched to an Apple laptop running Mac OS X it stopped working as the Mac drivers provided by HP don't seem to support network printing too well ... pretty ironic that only the Windows drivers work seamlessly with Apple's Airport Express!

I found a solution with open-source hpijs drivers. Here is how I made it work (follow the different steps in order):

1. Browse http://www.linux-foundation.org/en/OpenPrinting/MacOSX/hpijs
2. Download and install Ghostscript (find the appropriate version for you OS/system)
3. Download and install Foomatic RIP (find the appropriate version for you OS/system)
4. Download and install HPIJS (find the appropriate version for you OS/system)
5. Go to Print & Fax in the system preferences
6. Add your printer as a Bonjour printer, the computer should automatically select the corresponding Foomatic/HPJIS driver
7. You are done :-)

I assume the same will work with an Airport Extreme or a Time Capsule which are based on the same technology, and it applies to most HP printers (you can find a list of printers supported by the hpijs driver here).

Finally, to date I found only one drawback: the driver lets you select if you want to use the color or the black cartridge, but it is not possible to use both at the same time. This means that if you print color documents the blacks will be printed using a combination of color inks, and therefore they will be more dark grey than black and it will cost you more money.