Host details getting changed in Unisphere after host reboot

I am trying to configure a new ESX server to my Clariion CX4-240.

I have registered the host initiators with hostname - xxxxx and IP xx.xx.xx.xx

When i rebooted the host to install ESX 5.0 ,  the details changed to hostname - yyyyy and IP - yy.yy.yy.yy

PLease help