As the diagnostic says that eval is intermittently being passed an undefined value which it's trying to then parse as Perl. You need something beforehand to check for that case.

## Blah blah blah whatever populates $dumper
my $dump_error = undef;
my %info;
if( not defined $dumper ) {
  $dump_error = 1;
  warn qq{Got undefined from dumper.\n};
} else {
  %info = %{ eval $dumper };
}

## Do something like this to handle the error (or if %info was empty, 
+or . . .)
next if $dump_error or %info == 0;
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Edit: Of course rather than just calling warn (or whatever local logging routine is germane (e.g. Log::Log4perl)) with a static message you should of course dump out whatever other state you think might give you leads. Alternately rather than blithely trying to use the result from eval $dumper check that it worked first.

my $info_ref = eval $dumper;
if( $@ ) { 
  ## Similar notes about what you log apply here too, but . . .
  warn qq{Problem during dumper eval: $@\n};
} else {
  %info = %{ $info_ref };  ## Or just use $info_ref->{blah} rather tha
+n $info{blah}
}
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