The problem you are encountering is because the Java Development Kit is installed on this platform in ways that are different from the one on Linux. Thus the installation script fails to find all the necessary executables and ancillary files. However, there is an easy workaround which consists in setting an environment variable to point directly to the root of your Java installation. Here is how to proceed:

1. Download and unpack the pipeline kit of your choice (in your case, the VISIR one)
   
2. Set up the JAVA_HOME environment variable. According to our investigations, for your MacOS X 10.7 machine you should do this via the command:
   export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/
   Please make sure this is indeed the correct path. The script will expect to find two subdirectories in JAVA_HOME that are named 'Headers' and 'Commands', where the files 'jni.h' and 'javah' should be located, respectively.
   
3. Run the installation script 'install_pipeline'. The compilation should now go through after you have answered the initial questions about where you want the files installed.
   
4. Please make sure to set up the additional environment variables CPLDIR, DYLD_LIBRARY_PATH and PATH according to the instructions displayed at the end of the installation process. You should be able to copy/paste the suggested commands to achieve this. Issue also a 'hash -r' command after you have set the PATH variable (this step may not be necessary).
   
5. Just run 'gasgano' from the command line.