Do i need to add entry at /etc/hosts.allow ?
dbg : ALL

Basically, I want to develop php remotely through vpn connection.
win 98 client ---> vpn connection --> my remote linux server

After dialup vpn connection, I got the ip 192.168.15.202. Hence I can connect my remote local LAN.

I noted there is no response from server which is dbg enabled.
I tried to tcpdump on remote linux, no packets came out of port 7869.

My linux configuration:
Redhat 7.3, PHP 4.3.3, Apache 1.3.28

/etc/httpd/php.ini
extension=dbg.so-4.3.3RC1

[Debugger]
debugger.enabled=On
debugger.profiler_enabled=On
debugger.hosts_allow=localhost, 192.168.10.117, 192.168.15.202
debugger.hosts_deny=ALL
debugger.host=clienthost
debugger.port=7869
debugger.JIT_enabled=Off
debugger.JIT_host=clienthost
debugger.JIT_port=7869

I grabbed some text out of phpinfo();
Zend Engine v1.3.0, Copyright (c) 1998-2003 Zend Technologies with DBG
v2.11.23, (C) 2000,2001,2002,2003, by Dmitri Dmitrienko
dbg
DBG php debugger, version 2.11.23, Copyright 2001, 2002, Dmitri Dmitrienko,
www.nusphere.com/dbg
Version 2.11.23
Linked as a shared library.
Profiler compiled, enabled
Directive Local Value Master Value
debugger.enable_session_cookie On On
debugger.enabled On On
debugger.fail_silently On On
debugger.ignore_nops Off Off
debugger.JIT_enabled Off Off
debugger.JIT_host clienthost clienthost
debugger.JIT_level 3 3
debugger.JIT_port 7869 7869
debugger.profiler_enabled On On
debugger.session_nocache On On
debugger.timeout_seconds 300 300

my test page
<?php
$a=10;
echo $a;
DebugBreak();
function test ($x){
global $a;
$a = $x;
}
test(20);
echo $a;
?>

Thanks for your help.
wah

DBG Version 2.11.23 does not support security and therefore just ignores what have set in hosts_allow.
Try to run telnet as I proposed in FAQ/Troubleshooting posts (see in the topmost of PHPEd support forum)