Marketing Plan element Id Numbers missing if not saved?

Hi Folks,

Whenever I am creating a marketing project hierarchy(Marketing plans and elements),Say suppose I create a marketing plan element system automatically picks an ID for the marketing plan element  for ex.M-000010,if i dont save/cancel this marketing plan element and come out of the screen and next time when I want to create  a new Marketing plan element the system does not pick M-000010 but the next number M-000011.So M-000010 cannot be used again and even If I perform a search on M-000010 also it is not found in the result.Pls provide a solution if i dont want to miss/skip an Id like that?

Regards

Jaya