[techtalk] Telnet , ftp and imap problem

[Riton Roy]

Dear Sir

 We have Linux Server ( RedHat 6.1) ( Sendmail-8.9.3, Squid and DNS, ppp-on
and ppp-off). My
server connected to internet using dialup line by Modem with Telephone line.

My network TCP/IP base. Telnet and ftp and imap working from Linux Server.
But any PC under LAN it is not working.

How can I solved the problem. Do i need nay demon active?

Thanks
Riton