Currently, if lines beginning with a « * » (for <ul>'s) are separated by an empty line, they are rendered as separate <ul>'s.
i.e. "* foo\n\n* bar" is rendered as "<ul><li>foo</li></ul> <ul><li>bar</li></ul>"
We encounter a lot of cases like that, because contributors may think the wikisource is more readable so, and they don't notice the semantic failure.
In the case of "*", we can be pretty sure the contributor intended to make a single list. So I suggest we could be more tolerant and discard empty lines.
The case of "#" (<ol>) might require some examination of its uses on wikis before, but I think it may be readily feasible too.