Problem in Authentication with PGP

Hello members,

I have a problem in Nocat Authentication. Whenever I tries to access a
website from a client machine, it redirects to Nocat Login page. That
is fine. But when I enter user name and password, Internal server
error occurs, saying "Premature end of script". So, I looked into
authentication server's httpd log and I found that there is some
problem with gpg. Log is as follows:

====================================
gpg: Sorry, no terminal at all requested - can't get input, referer:
https://xxx.xxx.xxx.xxx/cgi-bin/login?redirect=http%3a%2f%2fwww%2egoogle%2eco%2ein%2f&timeout=300&gateway=155%2e155%2e155%2e10%3a5280&mac=00%3a02%3a72%3a04%3aC2%3a1F&token=%241%2458002409%24FvVzihiSmOX0q7fM6kBiM0

gpg --sign --armor --homedir=/usr/local/nocat/cgi-bin/../pgp
--no-secmem-warning --keyring trustedkeys.gpg --no-tty -o- returned
error: Illegal seek ( 2 ), referer:
https://xxx.xxx.xxx.xxx/cgi-bin/login?redirect=http%3a%2f%2fwww%2egoogle%2eco%2ein%2f&timeout=300&gateway=155%2e155%2e155%2e10%3a5280&mac=00%3a02%3a72%3a04%3aC2%3a1F&token=%241%2458002409%24FvVzihiSmOX0q7fM6kBiM0

Can't call method "text" on an undefined value at
../lib//NoCat/AuthService.pm line 135., referer:
https://xxx.xxx.xxx.xxx/cgi-bin/login?redirect=http%3a%2f%2fwww%2egoogle%2eco%2ein%2f&timeout=300&gateway=155%2e155%2e155%2e10%3a5280&mac=00%3a02%3a72%3a04%3aC2%3a1F&token=%241%2458002409%24FvVzihiSmOX0q7fM6kBiM0
====================================

This authentication server is not located in my internal network. But
my gateway is in internal  network. If this authentication server is
in my internal network it is working fine (I have setup authentication
server locally in my internal network for testing purpose also).

I also tried to synchronize clocks of my gateway server and
authentication server (remote one). But no success yet.

Any idea? Where am I making mistake ? Please provide comments.

Thanks,

Sanket Desai.