[R] using lattice dotplot with two equal data points

[Chosid, David (FWE)]

I'm wondering if I am dealing with a limitation in lattice.  It's
probably due to my own limitations though.  

I'm working with a lattice dotplot.  The x-axis is set at "free".  In
one panel, there are only two data points that have equal x-axis values.
Since no range exists, lattice isn't plotting those points. It reports: 

"Error Packet using 6 
'x' and 'units' must have length>0" 

Is there a way that I can get it to plot anyway?  Do I have to
manipulate that one panel?  Any suggestions on how to do that?  I'd
rather have some sort of automatic backup range set instead.

David Chosid
Massachusetts Division of Marine Fisheries
1213 Purchase St., 3rd Floor
New Bedford, MA 02740
508-990-2860 x140
email: david.chosid at state.ma.us