Macro in Word 2003 - Enter after a comma

For my job, I format resumes. In the resume there are a list of Technical Skills. What I would like to be able to do is create a Macro that will, after every comma, put the word on the next line. Basically enter after every comma. I then bullet them and put them into a three row column, which I have figured out how to do in a Macro. I have tried to look online but I am having troubles.

Thanks for any help you can give. I hope this was a good description of the issue.