where should the library go?

[kamaraju kusumanchi <raju.mailinglists@gmail.com>]

I am trying to package fortranposix as a debian package. The upstream is 
available at http://sourceforge.net/projects/fortranposix/

After compiling it, I get a file called libfortranposix.so. I am 
wondering whether this library should go into /usr/lib or 
/usr/lib/fortranposix directory?

I read the FHS standard and even then I am unable to figure out which is 
a better place.

any advice would be appreciated
raju