R help - May 2010 - Specify correlation structure in lme4

I know this was asked and answered in 2005, I just want to make sure the
answer still holds in 2010.

Question:

If I have the mixed-model with

lmer( y ~ x1 + x2 + (1 | id) + (z1 | w ) , ... )

there is no way for me to specify a correlation structure for the random
effects? Right?

If I want to specify correlation structure then I need to use lme in the
nlme package?  Right?  Crossed Random effects are coded with the pdBlocked
syntax?  Right?

Thanks,
-tgs

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Thomas Stewart <tgstewart <at> gmail.com> writes:
> If I have the mixed-model with
> 
> lmer( y ~ x1 + x2 + (1 | id) + (z1 | w ) , ... )
> 
> there is no way for me to specify a correlation structure for the random
> effects? Right?
> 
> If I want to specify correlation structure then I need to use lme in the
> nlme package?  Right?  Crossed Random effects are coded with the pdBlocked
> syntax?  Right?
   Right on all counts (see Pinheiro and Bates 2000 for details
of crossed-effect coding with pdBlocked). In general it might
be better to send these types of questions to r-sig-mixed-models
instead of r-help ...