Trellis (unwanted line)

["Keenan, Sean" <sean.keenan@citi.com>]

Dear Group;
I am using S-Plu 2000 Pofessional Release 1.  To consider the potential
importance of a variable left out of a regression (OPMAR is the variable), I
seek to plot it against some residuals grouping by industry (11 groups) by
issuing the command:
xyplot(d$residuals~mod$OPMAR|mod$IND).
This is fine, but it gives me un unwanted axis line halfway through the
rightmost column of panels.  Why does it do this and how can I make it stop?
Thanks,
Sean Keenan