Problems running anonymous platform

I'm trying to get my AMD64 machine with 64-bit Linux to run Einstein@home.
I've downloaded all three applications shown on the applications page and made the app_info.xml.
However, when I start Boinc I get the following error:

Mon Jan 1 17:16:20 2007|Einstein@Home|Found app_info.xml; using anonymous platform
Mon Jan 1 17:17:10 2007|Einstein@Home|Sending scheduler request to http://einstein.phys.uwm.edu/EinsteinAtHome_cgi/cgi
Mon Jan 1 17:17:10 2007|Einstein@Home|Reason: Requested by user
Mon Jan 1 17:17:10 2007|Einstein@Home|Requesting 8640 seconds of new work
Mon Jan 1 17:17:15 2007|Einstein@Home|Scheduler request succeeded
Mon Jan 1 17:17:15 2007|Einstein@Home|Message from server: To get more Einstein@Home work, finish current work, stop BOINC, remove app_info.xml file, and restart.
Mon Jan 1 17:17:15 2007|Einstein@Home|Message from server: No work sent

I have of course tried deleting the app_info.xml and restarting, as told, but get the message that the platform is not found (unknown-linux-gnu).
The strange thing is, Boinc removes the downloaded application einstein_S5R1... from the projects folder.

Are anonymous platforms no longer supported, or have I done something wrong?