I’ve searched for an answer but haven’t found one, so my problem is as follows: I turn on the Ruler, and then select “Show Line Numbers and Ruler”. The ruler is shown, along with a narrow gray margin on the left side. within this area there are the letters “jd” at the beginning of every paragraph. Line numbers are not shown, and I don’t know what “jd” refers too.
You are on Tiger. 
This is a bug that affects Tiger users only - I’ve fixed it for version 2.0.1 which should - hopefully! - be out later this week.
Thanks,
Keith