  Let $X$ be a separable Banach space endowed with a non-degenerate centered
Gaussian measure $\mu$ and let $w$ be a positive function on $X$ such that
$w\in W^{1,s}(X,\mu)$ and $\log w\in W^{1,t}(X,\mu)$ for some $s>1$ and $t>s'$.
In the present paper we introduce and study Sobolev spaces with respect to the
weighted Gaussian measure $\nu:=w\mu$. We obtain results regarding the
divergence operator (i.e. the adjoint in $L^2$ of the gradient operator along
the Cameron--Martin space) and the trace of Sobolev functions on hypersurfaces
$\{x\in X\,|\, G(x) = 0\}$, where $G$ is a suitable version of a Sobolev
function.
