Other way to a not supported inverse laplace transform with maxima?

On Mon, 2010-04-05 at 12:54 -0400, Benjamin Vanheuverzwijn wrote:
> I'm trying to calculate the inverse laplace transform of the following
> equation and it doesn't seem to work:
> ilt((15*%e^(-3*s)+15*%e^(-2*s)-15)/(2*s^2+4*s+34),s,t)
> 
> It is said it the documentation that "expr must be a ratio of
> polynomials whose denominator has only linear and quadratic factors.".
> As far as i know, (2*s^2+4*s+34) doesn't have "real quadratic factor".
your numerator is not a polynomial!

For instance, Maxima knows how to calculate:
ilt(1/s,s,t);

but it doesn't know how to calculate:
ilt(exp(-s)/s,s,t);

which any freshman student could obtain from the first one. I guess
nobody has had the time to improve ilt.
Regards,
Jaime