Jeg ved ikke helt hvad du vil frem til, men prøv at kig lidt i min kode:
-  <?php
 -  session_start();
 -  if(isset($_POST['submit'])){
 -      include("connect.php");
 -      
 -      function create($username, $usernameen)
 -      {
 -          $tid = date("d/m-Y H:i");
 -          
 -          $sql = "INSERT INTO log (username, datentime, remoteaddr) VALUES ('". $username ."', '". $time ."', 'xxx')";
 -          $query = mysql_query($sql) or die(mysql_error());
 -          
 -          $db_sql = "SELECT * FROM coworkers WHERE username = '". $usernameen ."'";
 -          $db_query = mysql_query($db_sql) or die(mysql_error());
 -          
 -          $db_row = mysql_fetch_assoc($db_query);
 -          if(base64_encode($username == $db_row['username']) && base64_encode($_POST['password']) == $db_row['password'])
 -          {
 -              $_SESSION['loggetind'] = "yes";
 -              $_SESSION['firstname'] = base64_decode($db_row['firstname']);
 -              $_SESSION['username'] = base64_decode($db_row['username']);
 -              $_SESSION['rank'] = base64_decode($db_row['rank']);
 -              $_SESSION['rights'] = $db_row['rights'];
 -              
 -              $newSql = "UPDATE coworkers SET lastentry = '". $tid ."' WHERE username = '". $_SESSION["username"] ."'";
 -              $newQuery = mysql_query($newSql);
 -              if(!$newQuery)
 -              {
 -                  die(mysql_error());
 -              }
 -              return "JEPS";
 -          }
 -          else
 -          {
 -              return "NEJ";
 -          }
 -      }
 -      $base64 = base64_encode($_POST["username"]);
 -      echo create($_POST["username"], $base64);
 -  }
 -  ?>