Piwik uses parse_url to split the url, then the excluded parameters are removed from the query-Result.
The problem is, that the ;jsessionid=... is still in the path-Result because it is separated by ; instead of ?
Example url: http://www.example.com/some/site.jsp;jsessionid=1234?param1=value¶m2=value
What's the best way to resolve this problem? Just replace/extend the parse_url function?
This was fixed in 2.16.1. See https://github.com/piwik/piwik/blob/3.x-dev/CHANGELOG.md#new-features-4