simplification preference



How would I make a rule or set a flag to tell Maxima that I would
prefer to have expression of this form:
(%e^(a*T)-1)/(z*%e^(a*T)-1)
changed to this:
(1-%e^(-a*T))/(z-%e^(-a*T))

Basically, if the expression includes exp(b*T), multiply numerator and
denominator by exp(-b*T) so that all exponentials of T are negative.
I came up with the second expression by visually inspecting the first,
using num and denom, multiplying the num and denom separately, using
expand and radcan on the denom and num separately and then setting the
new output:num/denom.  I would like to make a more general rule or
something, but don't know how.

Thanks,

Ryan