internet in virtual machine not running

[Tapas Mishra]

I have removed Network Manager Gnome from my Ubuntu which is a virtual
machine(Guest OS),I see the internet is no more running inside this
Virtual Machine.
While in other Virtual Machines (Other Linux) I had not removed
Network Manager Gnome and I see internet is running fine in them.

I am able to do an ssh into the vm in question irrespective of the
fact that it is not having any entry in /etc/network/interfaces
here are my firewall rules

# Generated by iptables-save v1.4.1.1 on Fri Oct 22 13:00:09 2010
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [287:55516]
-A INPUT -i lo -j ACCEPT
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
-A INPUT -j DROP
-A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied:
" --log-level 7
-A INPUT -j DROP
COMMIT
# Completed on Fri Oct 22 13:00:09 2010

 in the VM.I do not have any firewall on host machine and connected
without any proxy to internet.
 auto lo
iface lo inet loopback
iface eth0 inet static
address 192.168.1.4
netmask 255.255.255.0
gateway 192.168.1.1
pre-up iptables-restore < /etc/iptables.rules
 ifconfig
 ifconfig
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) What could be the problem?