My firm is currently using ACA 2010 for most of our production work that is not being done in Revit. Our template file has the IMAGEFRAME variable set to 2, so that the frames are visible but they do not print. (We have all of the "frame" variables set to 2, which can be done all at once by using the FRAME command.)
I have found, however, after starting a new drawing, that the frames around images will plot, particularly those nested within an externally referenced file. I double check the file, and IMAGEFRAME is set to 2, yet the border shows on my plot. I have no explanation for this, but I do have a workaround - if I set the value to 0 (do not show or plot the borders) and then back to 2, the setting "takes" and the borders remain visible but do not plot.