gfortran will be fine (backward compatible), but you might want to read the installation, README, or other documents. 

The error you received, essentially tells you that the make file is trying to execute the command 'defaultCompiler'. You will find that there is no such binary on your system. 

Usually there is a step in preparing a distribution prior to compiling that should replace 'defaultCompiler' with the appropriate command, e.g., gfortran or g77. It would appear that the step was not performed or not successful. Precisely what the step is, depends on the distribution. It is therefore impossible to say what should be done to correct it.

We would need a lot more information to fully help you. Usually defaultCompiler is a variable that should be replaced during configuration. Since the code seems to be fortran (*.F) you need some fortran compiler, typically g77 (gnu fortran 77) compiler on Linux.

But, as I indicated, it seems to me that your autoconf setup is not substituting appropriate variables to generate a valid Makefile. 

Again, much more detail required to be of any real help.

gfortran will be fine (backward compatible), but you might want to read the installation, README, or other documents. 

The error you received, essentially tells you that the make file is trying to execute the command 'defaultCompiler'. You will find that there is no such binary on your system. 

Usually there is a step in preparing a distribution prior to compiling that should replace 'defaultCompiler' with the appropriate command, e.g., gfortran or g77. It would appear that the step was not performed or not successful. Precisely what the step is, depends on the distribution. It is therefore impossible to say what should be done to correct it.

Hadi,

Let me restate. The error you are getting is one that indicates that the shell is trying to execute 'defaultCompiler'. No system has something called defaultCompiler. The error would occur regardless of the language being compiled, because if one types 'defaultCompiler' (without the quotes) at the command line, you will bet a similar error: "Command not found". 

This means that the system being used to configure the package for compiling did not substitute the path to, and name of, the appropriate compiler when you set the package up for compiling. Again, this is independent of the source code language. It occurred in the preparation steps prior to the make command. Usually there is a step required to configure the system. Sometimes there is an even earlier step that configures the configure script. 

The bottom line is that the error you are seeing is a system-level error that indicates a configuration problem.

Have you tried the following?

$sudo apt-get install build-essential gfortran or f77......

Does the package come with a configure script?  That is normal for an open source project - it runs a series of tests to determine the type of system you're using (OS level, hardware type, compilers available, system calls supported, etc).  It will also identify what is missing from your system that it needs in order to successfully build an executable.

When configure runs successfully, it will generate a valid Makefile and you can then run 'make' and have it all build successfully without any intervention.