docx and pdf files don't auto-tag


First off - fantastic idea for a tool! This could really assist in my organization's efforts. Here is my issue - I have installed SmartTag and configured it on a test library. The tool works as expected with .doc, .xlsx, .xls, .pptx, .ppt, and .txt files. However, .docx and .pdf extensions don't automatically tag. For instance, I have a file that I've saved in both .doc and .docx formats, and the .doc version of the file does tag automatically, the .docx version of the file fails to tag automatically.

Is there a solution that will allow automatic tagging of .docx files and .pdf files? Thanks in advance for any and all help.