[Rd] fork package problem

[billk01]

I have been using the fork package on a cluster to spawn jobs.  I have 
noticed that I end up with many "R defunct" (zombie) processes following 
the use of fork that do not die completely until I close down R.  
Initially, I thought it may be my code but I ran the example from the 
latest fork package (see code below) on R.2.3.1 and ended up with the 
same problem.  The code from the fork package that results in the R 
defunct processes is as follows:

{
pid = fork(slave=NULL)
if(pid==0) {
cat("Hi from the child process\n"); exit()
} else {
cat("Hi from the parent process\n");
}

I am running R-2.3.1 Suse10 linux but the same error also occurs with 
R.2.2.0.

I thought R-dev would be the most useful place but please suggest 
another mailing list if this is in appropriate.

Thanks,

Bill