[R] deriv() to take vector of expressions as 1st arg?

[t121 at gmx.net]

The deriv() function takes an 'expression' as its first argument). I was
wondering if the this function can take an array or a vector of
expressions as its first argument. Aside, I saw how to give a vector
argument to the second argument.

like to have something like:
deriv(c(~x^2+y^3, ~x^5+y^6), c("x","y"))

the documentation for this function talks about being able to "returns
the function values with a gradient attribute containing the gradient
matrix[!!!]". and I indeed want a matrix of expressions to be returned.

In effect, I want to get the Jacobian.

Thank you, if you have some hints on this.

Tom