I am very frustrated. I am having a very bad problem installing ANY third party library into my Mac. I am using Leopard, but the problem was also apparent in Tiger. I usually download a 3rd party library and I install it using ./configure and then "sudo make install". Although I see that the files have been installed inside "usr/local/include" (the headers are there!) when I try to make a new project and include those headers, XCode complaints that it can't file this file. However, I see that it is in its position! This has happened to me with Boost libraries and PCRE library. Same thing, same result. Any suggestions? Do I need to set any environment variables using terminal?