Building 5.1 from Source

[Ramakrishna Rallapalli]

 

        Hi,
         
            I am trying to build 5.1 from source. But unable to run the
build script. It looks for a download target in the build.xml file. And
its unable to check out the files from CVS erpository. Can anyone help
me out?
         
         Regards  ,
        Ramakrishna