This posting is older than 6 months and can contain outdated information.
As promised, here's an update:
What caused this issue:
The Mac OS X Update 10.6.5 contains changes in the USB area that renders the eHome/MCE driver's initialization routine defunct. In consequence, the receiver is not available to Remote Buddy.
Fix now available:
The new Remote Buddy version 1.16.6 ships with a new version of the driver that fixes this issue. You can either download and install the update from the Remote Buddy website or using Remote Buddy's built-in updater.
Please note that Remote Buddy will only be able to access your IR receiver after the new, bundled driver version has been installed and your system has subsequently been rebooted (this is needed for the updated driver to be used by OS X).
When you launch the new version, Remote Buddy will inform you about the new driver version and offer to install it.
Best regards,
Felix Schwarz