[R] seeing the code that is called inside a function

[markleeds at verizon.net]

this is probably a bad question but if
you type a function name( the function is from a package ) at
an R prompt and you see that the main work of the function is done by a fortran call (.Fortran ), is it possible to see the fortran code ? i am using windows xp and R-2.20 but i doubt that matters.

                                          thanks