Need help formatting phone numbers using Xmpie

[Kimba]

I'm completely knew to Xmpie, I went through one tutorial. I was asked to program a template and change the format of the phone numbers from 123-456-7890 to the 123.456.7890 I was trying to use the findandreplace function to do this but could not figure it out with the limited knowledge of the program. Can somebody tell me what I need to do?

Thanks
Kimba