diff -u pppd.orig/cbcp.c pppd/cbcp.c
--- pppd.orig/cbcp.c	2003-01-31 13:11:17.000000000 +0200
+++ pppd/cbcp.c	2004-09-25 17:54:21.407015232 +0300
@@ -464,7 +464,11 @@
 cbcp_up(us)
     cbcp_state *us;
 {
+/*******************************************************************************
+ Changed by Andrew Syreggelas (asyr) to permit to a single pppd
+ to request and receive a callback
     persist = 0;
+*******************************************************************************/
     lcp_close(0, "Call me back, please");
     status = EXIT_CALLBACK;
 }