No, per the doc there are the three (other than '-' and 'none') linestyle choices which, being one of the specific list of allowed string values, must match one of those given. There are no properties relating to the details of the line under that, hence there's no way to change that behavior.
All you can do is draw a specific line from the line primitive itself which will then actually be a set of individual lines.
All in all, the handle graphics objects really aren't very flexible; a pet peeve of mine is there is still no set of automagic hatch patterns.
