[Hplip-help] Cannot install hplip on RHEL 5

[Paolo G. <pga...@co...>]

Tried to install hplip-1.7.4a.run on a RHEL 5 system and it failed.  
Since RHEL 5 is not listed as a supported OS I told it it was a RHEL4 
system. I got the following error:

error: The distro/OS that you are running is unsupported and there are 
required dependencies missing. Please manually install the missing 
dependencies and then re-run this installer.
error: The following REQUIRED dependencies are missing and need to be 
installed before the installer can be run:
error: Missing REQUIRED dependency: libusb (libusb - USB library)

libusb is installed:

rpm -qa | grep libusb
libusb-0.1.12-5.1
libusb-0.1.12-5.1

The reason there are 2 entries is one for i386 and one for x86_64.

How do I add support for my Officejet 2605dn printer?

Thanks
Paolo