如何在Linux Ubuntu上使用2个不同版本的GCC并强制MAKE使用其中一个

I'm using the last version of Ubuntu which come with the gcc 4.4.5 version. I need to recompile a program that was not written by me and that can be only compiled with an older version of gcc like the 4.0. I managed to configure this older version and used a prefix during the install process so that my old gcc version is in the /opt/gcc-4.0.1/bin. I have tried to create a symlink using I'm using the last version of Ubuntu which come