Something wrong in my functions.php

[Abronsyth]

Well, here is the problemetic area:

PHP Code:

if(defined("SUBDIR")) include("../inc/config_forums.php");  
else include("inc/config.php"); 

//Now connecting to the adoptables database 
try{
  $adopts = new Database(DBNAME, DBHOST, DBUSER, DBPASS, PREFIX);
} 


On lines 6-12. Now, when trying to enter the ACP, here is what I am getting:
Could not connect to database, the following error has occurred:
SQLSTATE[HY000] [2005] Unknown MySQL server host 'DBHOST' (1)

---

Any clues as to what's wrong, and how to fix it?