diff --git a/include/hash2.h b/include/hash2.h
index 89c84c8..0a31fc5 100644
--- a/include/hash2.h
+++ b/include/hash2.h
@@ -61,7 +61,7 @@ void BX_clear_sorted_nicklist(NickList **);
 Flooding *BX_find_name_in_floodlist(char *, char *, HashEntry *, unsigned int, int);
 Flooding *BX_add_name_to_floodlist(char *, char *, char *, HashEntry *, unsigned int);
 
-unsigned long hash_nickname(char *, unsigned int);
+unsigned long hash_nickname(const char *, unsigned int);
 
 
 #endif
diff --git a/source/hash.c b/source/hash.c
index fc1297a..969f57f 100644
--- a/source/hash.c
+++ b/source/hash.c
@@ -44,9 +44,9 @@ CVS_REVISION(hash_c)
  * nick by counting up the ascii values of the lower case, and 
  * then %'ing it by NICKLIST_HASHSIZE (always a prime!)
  */
-unsigned long hash_nickname(char *nick, unsigned int size)
+unsigned long hash_nickname(const char *nick, unsigned int size)
 {
-        register u_char  *p = (u_char *) nick;
+	const unsigned char *p = (const unsigned char *)nick;
 	unsigned long hash = 0, g;
 	if (!nick) return -1;
 	while (*p)