Are you sure cc works on your Solaris system? Did you buy the compiler from Sun? Anyway, what Configure does to check if whether your compiler works and to see whether it's gcc or not is to compile and run the following program:

    #include <stdio.h>
    int main() {
    #ifdef __GNUC__
    #ifdef __VERSION__
            printf("%s\n", __VERSION__);
    #else
            printf("%s\n", "1");
    #endif
    #endif
            exit(0);
    }
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You might want to try compiling that from the command line.

-- Abigail