Trouble While Installing Joomla

HiI am using xampp 1.7.3 and joomla 2.5.1 full package. I extract joomla to C:xampphtdocsjoomla while visiting "LOCALHOST/joomla/installation/index.php#" it shows installation page. but by selecting language "English(US)" when i click to "Next" button it shows an error:"Install is undefined"on LOCALHOST/joomla/installation/index.phpHere "Install" is used in source script, called while clicking on "Next" button. the code is:<a href="#" onclick="Install.submitform();" rel="next" title="Next">Next</a>my browser suppors java, so that's not a problem. i do have "INSTALL" file in my "joomlainstallation" folder also. can u help me? what to do??