[R-sig-eco] envfit() in vegan

[Paolo Piras]

Dear list,
I write you because I do not understand the behavior of envfit() in vegan. 
Basically, it takes a matrix coming from an ordination procedure and it fits on it another matrix  (often an environmental matrix).
The projections of points onto vectors have maximum correlation with corresponding environmental variables.

A permutation test is associated to this procedure and it basically performs a series of correlations between any column in the environmental matrix and the ordnation matrix.
Maybe my question is trivial (or simply ...wrong) but..intuitively, this should return the same results found from a series of separate multivariate regressions between any single column in the environmental matrix and the entire ordination matrix.
However it is not the case, being the envfit() results much more liberal when compared to regression (i.e. using rda) and the r2 are drastically larger than R-sq from rda.
I suspect that the metric undergoing the permutation test of significance in envfit() that is squared correlation coefficient (r^2) does not correspond to the R-sq calculated using rda. 

Thanks in advance for any advice
best
paolo