[R] warning messages in grid or lattice give that I can't debug

[Richard M. Heiberger]

The messages are visible in 2.6.0dev
The same commands in 2.4.1 work without warning messages.
I am using the HH_1.18-1 from R_2.4.1 with both R versions and not
the current HH_2.1-3

version$version.string
installed.packages()[c("grid","lattice", "HH"),3]
## library(HH)
library(lattice, lib.loc="C:/PROGRA~1/R/R-2.4.1/library")
hotdog <- read.table(hh("datasets/hotdog.dat"), header=TRUE)
ancova(Sodium ~ Calories + Type, data=hotdog)


the messages in R_2.6.0dev are
Warning messages:
1: In grid.Call.graphics("L_points", x$x, x$y, x$pch, x$size) :
  supplied color is not numeric nor character
...
6: In grid.Call.graphics("L_points", x$x, x$y, x$pch, x$size) :
  supplied color is not numeric nor character


My guess is that these warnings are a response to a change in grid or lattice
in 2.5.0.  I attempted to trace these with 
options(warn=2)
options(error=recover)
without success.

Debugging suggestions or revised programming suggestions would be appreciated.

Rich