Fortran dy lib on Solaris

Dear all,

Am new on this list but need help:

I have a fortran code which I compile into a dynamic library (on Solaris).

My probem is that when I call this code soon after starting R, it runs ok. But 
it doesn't for the second time without exiting R first. In this code I have to 
generate some random numbers. The problem is not about setting the seed.

Anyone with an idea what might be going on?

Thanks,
Vysaul.