Message on the BouncStats home page:

2006-05-21: BOINCstats - URGENT: BAM and Linux hosts
Due to a small difference between AMS requests from Windows and Linux systems, BAM was unable to determine which project a Linux host was attach to. This problem is now solved, but this means that BAM has no record of attached projects for these systems, and BAM will order these hosts to detach from all projects.

To resolve this, you have to login to BAM, and check these hosts, and select the projects they should attach to.

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