cbp parameters introduced

modules/tm/t_hooks.h

@@ -142,6 +142,10 @@ typedef enum {
 	note that callbacks MUST be installed before forking
     (callback lists do not live in shmem and have no access
 	protection), i.e., at best from mod_init functions.
+
+	also, note: the callback param is currently not used;
+	if whoever wishes to use a callback parameter, use
+	trans->cbp
 */
 
 typedef void (transaction_cb) ( struct cell* t, struct sip_msg* msg, 

modules/tm/uac.c

@@ -281,8 +281,8 @@ static struct socket_info *uri2sock( str *uri, union sockaddr_union *to_su,
  *           'headers' parameter
  * - cb ..   callback to be called when transaction completes; if none
  *           present, no callback will be called
- * - cbp ..  callback parameter -- value passed to callback function
- *           when called
+ * - cbp ..  callback parameter -- value stored in transaction context
+ *           
  *
  */
 int t_uac_dlg(str* msg,                     /* Type of the message - MESSAGE, OPTIONS etc. */