I was just *stupid*.

Log::Log4perl implements a static object. Thus incrementing the caller_depth for each new logger instance is a very bad idea(tm).

Simply replace

# Increase value value of $Log::Log4perl::caller_depth by one
$Log::Log4perl::caller_depth++;  # NO NO NO!!!
[download]

With this:

  # Set value of $Log::Log4perl::caller_depth to one. Since Log4perl's
  # logger is a static object, the value must not be increased more
  # than once.
  $Log::Log4perl::caller_depth = 1;
[download]

Andreas
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