If you were worried about this you could collect the parameters like this :-

  my $hash = {};
  for ($cgi->param())
  {
    push @{$hash->{$_}}, $cgi->param($_);
  }
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However I find that 9 times out of 10 you want the simpler hash, so you can collect the data twice in a slightly more complicated way something like this :-

  my $hash = {};
  for ($cgi->param())
  {
    push @{$hash->{list}->{$_}}, $cgi->param($_);
    $hash->{scalar}->{$_} = $hash->{list}->{$_}->[0];
  }
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You can then access most data with a simple $hash->{scalar}->{'whatever'} but for those cases when you cared about multiple entries you can do $hash->{list}->{'whatevers'}->1

I think the CGI module is fantastic, but I do find it much more convenient to have my data in a hash rather than have to call it from param() when I need it. For a CGI of any length then I'd certainly use one of another of the methods above.