diff -p -u -r WordNet-3.0/lib/morph.c WordNet-3.0-mine/lib/morph.c
--- WordNet-3.0/lib/morph.c	2010-04-12 13:53:04.000000000 +0200
+++ WordNet-3.0-mine/lib/morph.c	2010-04-12 13:54:53.000000000 +0200
@@ -375,14 +375,14 @@ static char *exc_lookup(char *word, int 
     static char line[WORDBUF], *beglp, *endlp;
     char *excline;
 
-    if (exc_fps[pos] == NULL)
+    if (exc_fps[pos-1] == NULL)
 	return(NULL);
 
     /* first time through load line from exception file */
     if(word != NULL){
         if (strlen(word) > WORDBUF - 1)
            return(NULL);
-	if ((excline = bin_search(word, exc_fps[pos])) != NULL) {
+	if ((excline = bin_search(word, exc_fps[pos-1])) != NULL) {
 	    strcpy(line, excline);
 	    endlp = strchr(line,' ');
 	} else