when you see those errors -- fatal errors -- that means your script will most likely not function as advertised in certain, potentially critical points.
For you to not care that your code is coughing up these errors is sloppy. Why bother loading Mime::Lite if its dependencies aren't met?
Take everybody's advice and either satisfy Mime::Lite's requirements. When you say
I believe many of the modules that Mime::Lite uses are optional and I don't use them so I guess that why it works...
you should be a little sad. Know how your script works and know what's required. If you're resorting to guessing why it works, you're going to be well and truly baffled when it breaks.