Recently I have experienced issue with Rich Text Editor in Sitecore which is based on Telerik Editor. Sometimes creating numbered/non-numbered list from RTE caues problems.
I have attached link to RTE_edit.swf - in 1:07 there is showed how the issue looks.
Guys from Sitecore support provided me with some resolution, but it does not work well :(
Do you have any clue how it can be resolved? Or maybe you can provide the code for InsertOrderedList and InsertUnorderedList commands?