[R] lmer and correlation

[R Help]

Hello list,
     I've been reading through the archives and it seems as though, as
of right now, there is no way to specify the correlation structure in
lmer.  I was wondering if anyone knows if this is going to be
implemented?  I'm using mixed-effects models within a tree structure,
so I make a lot of calls to lme to get the resulting deviance, and
lmer2 is almost 5 times faster than lme on my test data, so if it may
be implemented later I'd be willing to wait, otherwise I might look
into trying to hack it myself.

Sam Stewart