I have ESXi 5.0 installed and when I am installing Ubuntu Server 12.04 LTS (32 bit) it is giving an error saying grub installation failed

Here is a screenshot of the error:

1. I have other Ubuntu servers running fine on this esxi server, so I don't think problem is with ESXi.
   


2. I have 32 GB of ram spare on this ESXi and have given 2 GB of RAM to this 12.0 LTS VM.


3. I have allocated 2 processor cores.


4. I have tried supplying different ISO Image to this VM as I thought the 1st image that I downloaded has errors. But that's definitely not the case as all 3 different ISO images that I downloaded of Ubuntu server 12.04 LTS (32-bit) can't be corrupt!


5. Just to make sure that the Image does not have problem I used that Image to install it for testing on stand alone system. it works fine there!


6. This is a production ESXi server which I can't play with, however I can play with the Ubuntu Server 12.04 LTS (32-Bit) VM that we have created on that ESXi.
   

Here is more information for another attempt:

• For this install, I've given 1 core of the XENON processor, 1 GB of RAM and 20 GB of HHD.




• I have used LVM with the automatic partition manager (where I do not have to create partitions manually).




• I do not have any working Ubuntu 12.04 LTS image installed anywhere. :(




• I tried installing Ubuntu 12.10 on the same VM which worked well, however that is of no use to me as I need Ubuntu 12.04 LTS only for testing purpose.

Please let me know if you need any further details. 

I need help on this as soon as possible, as the go live date of this server is really close.