Then you can name this script, after changing "tag_of_utc" and "onenter_old", to the onEnter script for your module and then create a copy of the old onEnter script and rename it.
void main() {
// Check to see if it has already been spawned
if(!GetIsObjectValid(GetObjectByTag("tag_of_utc")))
CreateObject(OBJECT_TYPE_CREATURE, "dan13_deesra", Location(Vector(60.82,46.78,4.92), 0.0));
// Fire old script
ExecuteScript("onenter_old", OBJECT_SELF);
}
Hope that helps, and it is worth reading through the thread Stream suggested. ;)
http://www.lucasforums.com/showthread.php?t=143536)