搞了一下午，原来就这样。。
以下是原文，链接如下：
http://bryan.parno.net/thoughts/?p=49
Satisfying IEEE PDFexpress
IEEE has started using a service called PDFexpress for the camera-ready versions of conference papers. You can use it to convert a variety of formats to PDF, or you can have it check your PDF for compatibility.
When I checked our paper for compatibility, it complained about two items:
Acrobat version is less than 5.0
Font Times-Italic, Times-Bold, Times-Roman, Helvetica, Courier, Helvetica-Oblique, Helvetica-Bold, Symbol is not embedded
This was resolved using the following series of flags for ps2pdf:
ps2pdf -dCompatibilityLevel=1.4 -dEmbedAllFonts=true -dPDFSETTINGS=/prepress
I believe the first flag solved the version problem, the second flag solved the fonts problem, and the third flag supposedly enhances the output quality for use on a printing press.
