Your Linux application is linked against glibc 2.4 so it crashes on startup when run on older machines/distributions.

3 possibilities:

1) Detect this and refuse to run
I would not prefer this because it means losing the CPU power of these clients, besides it would be advisable to detach the machine from the project automatically in this case, if not it will waste CPU and download bandwidth with repeated failing attempts.

2) Compile against glibc 2.3
If glibc 2.4 makes the programme faster on many machines this is also not good.

3) Link it statically
This is preferabele: it will then run on any machine with a suitable boinc client, no matter which libc is installed.

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