If a nodes-date is set to (lets say) 30th of January 2010 and you try to repeat this node then there won't be any entries for February.

The same is also happening if the day is the 31st of a month. There won't be any repeats for months that don't have 31 days but have 30.

I believe that this problem should be addressed and entries should be added on the last day of each month if the month doesn't have more days.