PXE boot problems in Solaris 10

Hi folks, I was trying to setup Network based NFS installation with PXE.
I'm using virtual box for this purpose. I have one redhat (DHCP) server and Solaris 10 (Install server - Source) and on the other one am trying to install solaris using PXE. As in, dhcp address and boot file can be fetched using Redhat server from Solaris 10 (Install server). Thing is, when I start the new solaris VM it's trying to get IP and it fails with PXE access violation. I don't know what's the problem. /tftpboot has full permissions expect one directory cos that has been mounted from CDROM I guess. Please advise. Necessary screenshots attached. Helps would be appreciated.

Is there some particular reason you are using Red Hat as the DHCP Server? Somewhere in the back of my mind, I vaguely recall that your setup combination is problematic.

There's no specific reason for me to configure DHCP on redhat other than it's modest and easy. Do you think that's the problem here ? If that's the case it wouldn't supply the IP address itself right ? Any ways, I'm honoring your response. Go ahead and suggest the solution for this.