How to make Photoshop save Aperture imported JPEG images as JPEGs

[clappernicus]

Recently, I upgraded from Photoshop CS 5 to CS 5.1.
 
My point and shoot cameras record in JPEG format. Often, I'll import those photos into Aperture and then tweak them in Photoshop using the Edit in External Editor command. My preferences for the external editor in Aperture were set to 8-bit, Photoshop
 
With Photoshop CS 5, I would edit the photo and choose Save and the edited photo would be saved back to Aperture as a new version, in a JPEG format.
Now, using Photoshop CS 5.1, when the imported image from Aperture is converted into a PSD file and when I save back to Aperture, I end up with a PSD file.
 
How can I revert to how it was before? JPEG image in Aperture, opened in external editor Photoshop as a JPEG, edited in Photoshop, then saved back to Aperture as a new version JPEG?
 
(Though this question is approached in this forum, a solution to my question is never found as each dicussion ends up going off-topic from the original question)

[JohnNewman]

I haven't now got CS5 installed on my Mac but I am 99.5% sure that it was never possible to use CS5 as an external editor and have the edits automatically saved back into Aperture as a jpeg.  I am sure that the only options have always been either PSDs or TIFFs, and you could choose either 8 or 16 bit.

If I wanted to save space, I then exported the saved file as a full size jpeg, and then re-imported back into Aperture and deleted the PSD/TIFF. It would have been nice to have the jpeg option and I have seen plenty of threads elsewhere bemoaning the lack so I'm pretty sure this has been the case for a long time (if not always).  Others may prove me wrong and, if so, I apologise but I just can't remember jpeg as an option in any version of Aperture.  If you're still using the same version of Aperture, then a quick check in Preferences will show the options which won't have changed just because you're using a different version of Photoshop as the options apply for any external editor, not just Photoshop.

Regards

John.

p.s. iPhoto, of course, is a different kettle of fish altogether.