[R] logistic regression for repeated measurement

[Hiroto Miyoshi]

Dear R-users

I need your help.
I have a data set which was collected from 
an experiment of one between- and one 
within-subject design. And the response 
data is coded by success(1)/failure(0).

The experiment had two groups of subjects:
The one was experimental, and the 
other, control.  The experimental group
got a task training, and both groups of subjects
were tested twice, once before the training
and once after the training. at the same time.
I like to examine the effect of training by
detecting an interaction effect of the group and 
tests. 
Now, it seems glm is not appropriate to this 
situation since it does not deal with stratified
errors.

Could you lead me to appropriate functions?
Sincerely
-----------------------
Hiroto Miyoshi
三好弘人
h_m_ at po.harenet.ne.jp