multiple page postscript

Hi,
I'm new to matplotlib, I'm trying to save a series of plots in a single postscript files. Is that possible?
I'm able to save each single plot in a different file using savefig, but I'd like my script to save the plots in a single ps file with more pages. Is there anyway to open a ps file, send the output of the plot() command to it and close it as the script ends?

Thanx
Cheers
Gabriele