rpmInstall error: no dbpath has been set

[Mathieu Dube <mdube 8D com>]

Hi,
	what does it mean if I call rpmInstall(from rpmlib) and the 
output is : error: no dbpath has been set?

I tried "","/" and "/var/lib/rpm" for the first argument to rpmInstall and 
it didnt work so I assume there's another function I should call before
doing that

Thanks
-Mat