customize 503 error page in IIS Tomcat configuration

Hi Team,

For the IIS tomcat configuration, i need to customize the 503 error message which is present in 'isapi_redirect.dll'.

DLL file which i am using :
http://apache.thelorne.com/tomcat/tomcat-connectors/jk/binaries/win32/jk-1.2.30/isapi_redirect-1.2.30.dll

DLL source code :

http://apache.thelorne.com/tomcat/tomcat-connectors/jk/source/jk-1.2.30/tomcat-connectors-1.2.30-src.zip

I modifed the source code of 'isapi_redirect.dll' and re-build using Visual studio 2008 ( release mode ) on windows xp machine.

while compiling and building there were just fine. no error or warning were displayed.

but i put the same .dll file in IIS, i realized that dll was not working and blank page is being displayed.

I am stuck in this for couple of days.

could you please help in resolving this issue.