R help - Feb 2003 - "deriv" and chain rule and matrix derivatives

Hi,
Anybody knows if I can use "deriv" to implement CHAIN RULE AND MATRIX
derivation.
Simple examples:

y=expression(log(x))
z=expression (x*y)
deriv(z,"x") # chain rule

f=expression(det(x)) # where x is an (nxn) matrix
deriv(f, "x")

Is there any way to work around this?

Thank you very much.

Ahmad Abu Hammour

PS. by the way I tried to send the same email using my http-based account
hammour at msn.com, but I could not, although I set send email to plain text.