Problems with PPP server. Unable to ping the remote host when it loggs in.

[ejff]

I have set up the ppp server. When somebody calls to me, the connection establishes and the PPP server gives IPs to my machine and to the remote host.
First the remote host couldn't even ping me. Then i have set up a few filters in the ppp configuration file, that allow any ICMP, TCP, and UDP traffic in and out.
After this, the remote machine became able to ping me, watch my sites, and so on.

!!! The main problem is that i am unable to ping the remote machine !!!

PING tells me that there is no route to the remote host.

i have FreeBSD 4.4-RELEASE
PPP version: 2.3.2