sub session_create
{
  my ($obj, $dbh, $userid) = @_;
  my $mydbh = $dbh;

  unless($mydbh) { $mydbh = &libyn::DB::connect_to_db($obj); }

  $CGI::Session::MySQL::TABLE_NAME = $libyn::Config::DbTables{sessions};
  my $session =  CGI::Session->new("driver:MySQL", $obj->{-cgi}, { Handle => $mydbh }) or die "CGI::Session->new failed.";
  $session->name('sessionId');
  $session->expire('+1h');
  $session->param('userId', $userid);

  unless($dbh) { $mydbh->disconnect(); }

  return $session;
}