[R-SIG-Mac] how does one dyn.load dylib shared libraries?

[Richard Tabor]

I am running 2.1.0 and am using the IBMXL Fortran Compiler.  It has .a 
and .dylib libraries which do not seem to load with dyn.load(). 

Is there a way to load these libraries or convert them to .so's? 

Thanks.

Richard