Natty,
Had to make slight modifications and it worked!
The actual problem was if you do server.transfer to a page which is having an asp.net validations control the WebUIvalidations.js is not loaded some times and it displays an error stating to reinstall the js file by running aspnet_regiis -c command.
The possible solution for this problem is add this code from where you are performing server.transfer.
//ASP.NET bug fix which causes script file not to bind with page
string sEnvVersion=Environment.Version.ToString();
//From 1.0.3705.288 To 1_0_3705_288
sEnvVersion = Regex.Replace(sEnvVersion,"[.]","_");
//Register the client script
RegisterClientScriptBlock("BlockID","<script language=\"javascript\" src=\"/aspnet_client/system_web/"+sEnvVersion+"/WebUIValidation.js\"></script>");
Cheers
nitc3