Is it appropriate for a professor to give the same exam to two different classes 2 weeks apart? Is it appropriate for a professor to give an exam to section A and then give the same exact exam to section B 2 weeks later?

Would this be a proper argument towards the professor and/or university to either curve or do something about the grades of the two sections?

It's an engineering course with the same prof in both sections.

(note: in the original version sections A and B are called "the English section" and "the French section", respectively, but these names have been edited out because they seem to be a red herring.)
I deduce that one section is taught in French and another section is taught in English? The tests should be given in the language that the class is taught in. However, if there is reason to believe that all students are fluent in one language (e.g. English), it is debatable whether the language of the exam is actually of consequence. 

Does your university require all students to be competent in English (or in French)? I guess it could be argued that students who only speak English should not be required to take a test in French. 

Seeing as this is an engineering course, it would seem that there would not be a significant advantage to students who attend the French section versus the English section.