problem linking libjpeg

I am using libjpeg functions in my program, everything seems okay in the make, but when it comes to linking, although the libjpeg.a is in the list of modules and libraries given to cc, it keeps telling me that all symbols from libjpeg that i use in my code are not found..

Someone could help ?
Thanks !

I found that you get this if your program objects were compiled as C++ but the libjpeg was compiled as C.
I fixed it by simply renaming the libjpeg source files to .cpp (there is probably a proper way to do it that I don't know of).