Submitted to TclX developers as:

https://sourceforge.net/tracker/index.php?func=detail&aid=2687373&group_id=13247&atid=313247

	-mi

--- generic/tclExtend.h	2002-09-25 20:23:29.000000000 -0400
+++ generic/tclExtend.h	2009-03-14 17:57:46.000000000 -0400
@@ -123,19 +123,19 @@
 EXTERN int	TclX_KeyedListGet _ANSI_ARGS_((Tcl_Interp *interp,
 			       Tcl_Obj	  *keylPtr,
-			       char	  *key,
+			       const char *key,
 			       Tcl_Obj	 **valuePtrPtr));
 
 EXTERN int	TclX_KeyedListSet _ANSI_ARGS_((Tcl_Interp *interp,
 			       Tcl_Obj	  *keylPtr,
-			       char	  *key,
+			       const char *key,
 			       Tcl_Obj	  *valuePtr));
 
 EXTERN int	TclX_KeyedListDelete _ANSI_ARGS_((Tcl_Interp *interp,
 				  Tcl_Obj    *keylPtr,
-				  char	     *key));
+				  const char *key));
 
 EXTERN int	TclX_KeyedListGetKeys _ANSI_ARGS_((Tcl_Interp *interp,
 				   Tcl_Obj    *keylPtr,
-				   char	      *key,
+				   const char *key,
 				   Tcl_Obj   **listObjPtrPtr));
 
--- generic/tclXkeylist.c	2005-11-21 13:54:13.000000000 -0500
+++ generic/tclXkeylist.c	2009-03-15 00:43:31.000000000 -0400
@@ -121,9 +121,9 @@
 				  int		entryIdx));
 
-static int
+static intptr_t
 FindKeyedListEntry _ANSI_ARGS_((keylIntObj_t *keylIntPtr,
-				char	     *key,
+				const char   *key,
 				int	     *keyLenPtr,
-				char	    **nextSubKeyPtr));
+				const char  **nextSubKeyPtr));
 
 static void
@@ -342,5 +342,5 @@
     int		  entryIdx;
 {
-    int idx;
+    intptr_t idx;
 
 #ifndef NO_KEYLIST_HASH_TABLE
@@ -348,5 +348,5 @@
 	Tcl_HashEntry *entryPtr;
 	Tcl_HashSearch search;
-	int nidx;
+	intptr_t nidx;
 
 	entryPtr = Tcl_FindHashEntry(keylIntPtr->hashTbl,
@@ -364,5 +364,5 @@
 	for (entryPtr = Tcl_FirstHashEntry(keylIntPtr->hashTbl, &search);
 	     entryPtr != NULL; entryPtr = Tcl_NextHashEntry(&search)) {
-	    nidx = (int) Tcl_GetHashValue(entryPtr);
+	    nidx = (intptr_t) Tcl_GetHashValue(entryPtr);
 	    if (nidx > entryIdx) {
 		Tcl_SetHashValue(entryPtr, (ClientData) (nidx - 1));
@@ -397,13 +397,14 @@
  *-----------------------------------------------------------------------------
  */
-static int
+static intptr_t
 FindKeyedListEntry (keylIntPtr, key, keyLenPtr, nextSubKeyPtr)
     keylIntObj_t *keylIntPtr;
-    char	 *key;
+    const char	 *key;
     int		 *keyLenPtr;
-    char	**nextSubKeyPtr;
+    const char	**nextSubKeyPtr;
 {
-    char *keySeparPtr;
-    int keyLen, findIdx = -1;
+    const char *keySeparPtr;
+    int keyLen;
+    intptr_t findIdx = -1;
 
     keySeparPtr = strchr (key, '.');
@@ -417,18 +418,17 @@
     if (keylIntPtr->hashTbl != NULL) {
 	Tcl_HashEntry *entryPtr;
-	char tmp = key[keyLen];
+	char *tmp;
+	const char *_key;
+
 	if (keySeparPtr != NULL) {
-	    /*
-	     * A few extra guards in setting this, as if we are passed
-	     * a const char, this can crash.
-	     */
-	    key[keyLen] = '\0';
-	}
-	entryPtr = Tcl_FindHashEntry(keylIntPtr->hashTbl, key);
+	    tmp = alloca(keyLen + 1);
+	    strncpy(tmp, key, keyLen);
+	    tmp[keyLen] = '\0';
+	    _key = tmp;
+	} else
+	    _key = key;
+	entryPtr = Tcl_FindHashEntry(keylIntPtr->hashTbl, _key);
 	if (entryPtr != NULL) {
-	    findIdx = (int) Tcl_GetHashValue(entryPtr);
-	}
-	if (keySeparPtr != NULL) {
-	    key[keyLen] = tmp;
+	    findIdx = (intptr_t)Tcl_GetHashValue(entryPtr);
 	}
     }
@@ -556,5 +556,6 @@
     keylEntry_t *keyEntryPtr;
     char *key;
-    int keyLen, idx, objc, subObjc;
+    int keyLen, objc, subObjc;
+    intptr_t idx;
     Tcl_Obj **objv, **subObjv;
 #ifndef NO_KEYLIST_HASH_TABLE
@@ -720,9 +721,9 @@
     Tcl_Interp *interp;
     Tcl_Obj    *keylPtr;
-    char       *key;
+    const char *key;
     Tcl_Obj   **valuePtrPtr;
 {
     keylIntObj_t *keylIntPtr;
-    char *nextSubKey;
+    const char *nextSubKey;
     int findIdx;
 
@@ -775,11 +776,12 @@
     Tcl_Interp *interp;
     Tcl_Obj    *keylPtr;
-    char       *key;
+    const char *key;
     Tcl_Obj    *valuePtr;
 {
     keylIntObj_t *keylIntPtr;
     keylEntry_t *keyEntryPtr;
-    char *nextSubKey;
-    int findIdx, keyLen, status = TCL_OK;
+    const char *nextSubKey;
+    intptr_t findIdx;
+    int keyLen, status = TCL_OK;
     Tcl_Obj *newKeylPtr;
 
@@ -901,9 +903,10 @@
     Tcl_Interp *interp;
     Tcl_Obj    *keylPtr;
-    char       *key;
+    const char *key;
 {
     keylIntObj_t *keylIntPtr, *subKeylIntPtr;
-    char *nextSubKey;
-    int findIdx, status;
+    const char *nextSubKey;
+    intptr_t findIdx;
+    int status;
 
     if (Tcl_ConvertToType (interp, keylPtr, &keyedListType) != TCL_OK)
@@ -975,11 +978,12 @@
     Tcl_Interp *interp;
     Tcl_Obj    *keylPtr;
-    char       *key;
+    const char *key;
     Tcl_Obj   **listObjPtrPtr;
 {
     keylIntObj_t *keylIntPtr;
     Tcl_Obj *listObjPtr;
-    char *nextSubKey;
-    int idx, findIdx;
+    const char *nextSubKey;
+    int idx;
+    intptr_t findIdx;
 
     if (Tcl_ConvertToType (interp, keylPtr, &keyedListType) != TCL_OK)