I am having similar problems, and I think that this is an Adobe issue and not an Apple issue. I have been trying to print off PDF documents that have been scanned with our printer/scanner/copier/fax machine at work. The machine sends the scanned documents as PDFs to selected email addresses.
I have my email client set up to use Adobe Acrobat to open and print PDF files. I am running OS X 10.8.2 and Adobe Acrobat Pro 11.0.0. I'm using Postbox as my email client, but that is unimportant since I am opening the files from from the Downloads directory directly.
I can print these PDFs okay when I print using Preview. When I try to print them using Adobe Acrobat Pro, I get the "unable to convert Postscript file" error, and I get this error whether printing to my HP Color Laserjet 2600N or my Canon MX510.
To me, this indicates two possibilities:
Apple has done something (likely inadvertantly) to prevent printing Postscript files using anything but Preview, or (in my opion more likely)
Adobe has some bug in their Acrobat products that prevents printing of Postscript files under ML.
Cheers,
hussar