R help - Feb 2005 - lme4--->GLMM

Hello,

I'm very sorry for my repeated question, which i  asked 2 weeks ago, namely:

i'm interested in possibly simple random-part specification in the call 
of GLMM(...)   (from lme4-package)
i have a random blocked structure (i.e. ~var.a1+var.a2+var.a3, 
~var.b1+var.b2,~var.c1+var.c2+var.c3+var.c4),
and each one part of it i would like to model as Identity-structure 
matrix. So i had, in symbols of nlme-package,
and for only one cluster-variable my.Subject:

random=list(my.Subject=pdBlocked(list(pdIdent(~var.a1+var.a2+var.a3,...),pdIdent(~var.b1+var.b2,...),pdIdent(~var.c1+var.c2+var.c3+var.c4),...)))

As the lme4-package doesn't use the pdMat-classes for specification of 
the random-part in GLMM,    i used,  with advice of Douglas Bates,
the explicit specification in the GLMM-call (this call can also been 
simplified, if i first attach the lme4 package and then the nlme-package):

GLMM(....., random=list(my.Subject=~var.a1+var.a2+var.a3, 
my.Subject=~var.b1+var.b2, my.Subject=var.c1+var.c2+var.c3+var.c4),.....)

and really could make estimates in such a way.

The problem is how can i specify  a simple matrix sructure for each  
block, such as pdIdent(...) in symbols of lme4. is it possible? 
Does the lme4 any use of pdMat-specification or something like this? If 
not, it seems, that i actually specify a general Covariance Matrix
for each block, what i in principle don't want.

thanks in advance