How do I collect binary files with nxlog?

Question

My program occasionally produces non-text binary files, ~5MB in size. I want to collect these in nxlog.

I tried using Module im_file with InputType binary (nxlog.conf below), but this gets me error: binary header not found at position 0 in data received from <my.bin>, is input really binary?

<Input in_binary>
    Module im_file
    File "C:\\path\\to\\*.bin"
    ReadFromLast False
    SavePos False
    Recursive False
    InputType binary
</Input>

<Output out_binary>
    Module om_file
    File "C:\\path\\to\\output\\binary_data.bin"
</Output>

<Route route_binary>
    Path in_binary => out_binary
</Route>