Configure floating IP on loopback interface

Hi All,

I need to configure a floating IP on loopback interface of two servers (RHEL 5.4). After configuring, I'm not able to ping to that IP from a different server.
I fail to understand what is missing here. I have done similar configuration in another environment & it works fine.
Plz help.

### Command to add the virtual IP ###
/sbin/ip addr add 192.168.121.190/32 scope host dev lo
----------------------------------------------
### ip addr o/p after addition ###
# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
    inet 192.168.121.190/32 scope host lo
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 00:21:5e:dd:02:60 brd ff:ff:ff:ff:ff:ff
    inet 192.168.121.176/24 brd 192.168.121.255 scope global eth0
    inet6 fe80::221:5eff:fedd:260/64 scope link
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop qlen 1000
    link/ether 00:21:5e:dd:02:62 brd ff:ff:ff:ff:ff:ff
4: usb0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
    link/ether 02:21:5e:df:82:63 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::21:5eff:fedf:8263/64 scope link
       valid_lft forever preferred_lft forever
5: sit0: <NOARP> mtu 1480 qdisc noop
    link/sit 0.0.0.0 brd 0.0.0.0
----------------------------------------------

### ifconfig -a o/p ###

eth0      Link encap:Ethernet  HWaddr 00:21:5E:DD:02:60
          inet addr:192.168.121.176  Bcast:192.168.121.255  Mask:255.255.255.0
          inet6 addr: fe80::221:5eff:fedd:260/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:11213 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3609 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:880542 (859.9 KiB)  TX bytes:382504 (373.5 KiB)
          Interrupt:169 Memory:92000000-92012800

eth1      Link encap:Ethernet  HWaddr 00:21:5E:DD:02:62
          BROADCAST MULTICAST  MTU:1500  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:1000
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:106 Memory:94000000-94012800

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:2701 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2701 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:4144416 (3.9 MiB)  TX bytes:4144416 (3.9 MiB)