NAs spoil lowess smoothing

Can anyone explain to me what this error message means, why I'm getting it, and
how to fix it?

 lines(lowess(xdat, ydat, f=.5), col=3)
Error: NAs in foreign function call (arg 1)
______________________________________________________________________
Stuart Luppescu         -=-=-  University of Chicago
ºÍʸ ¤ÈÃÒÆàÈþ¤ÎÉã(EUC)  -=-=-  s-luppescu at uchicago.edu
http://www.consortium-chicago.org/people/sl/sl.html
ICQ #21172047  AIM: psycho7070
The program isn't debugged until the last user is dead.

Sent on 28-Jan-99 at 11:26:00 with xfmail

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