error in hetcor function (polycor package)?

I have been using the hetcor function in the polycor package.  When I
don't specify the use option everything runs smoothly.  However, when I
specify use either as "pairwise.complete.obs" or "complete.obs" I get
this error
 
Error in optim(rho, f, control = control, hessian = TRUE, method =
"BFGS") : 
        non-finite value supplied by optim

Is this an error in the hetcor function or am I missing something. 
Thanks for your help.
 
Brendan Klick
Johns Hopkins University School of Medicine