R help - Aug 2010 - Tukey post hoc test and two way repeated measures ANOVA

Dear all,

I have  a serious problem  in applying Tukey post hoc after a repeated 
measure ANOVA. I
followed the suggestions  that I found in this  help -list  especially
this one:

//[R] Tukey HSD (or other post hoc tests) following repeated measures ANOVA

You want to use lme() in package nlme, then glht() in the multcomp package.
This will give you multiplicity adjusted p-values and confidence intervals.

## Example
require(MASS)         ## for oats data set
require(nlme)         ## for lme()
require(multcomp)  ## for multiple comparison stuff

Aov.mod <- aov(Y ~ N + V + Error(B/V), data = oats)
Lme.mod <- lme(Y ~ N + V, random = ~1 | B/V, data = oats)

summary(Aov.mod)
anova(Lme.mod)

summary(Lme.mod)
summary(glht(Lme.mod, linfct=mcp(V="Tukey")))

HTH, Mark./

My problem is that in my study I want to test the interactions among
different levels of two predictors. Considering, for example, oats 
dataset in MASS
package how can I test the contrast between one level of the variable V
(for example, Victory) and one level of the variable N(for example 0.0cwt)?

Please, help me!

Nicola