Why do some sets have two different numbers? Possible Duplicate:
  Why did Lego use the same number for two different sets?  




For example, 324 Ricky Racoon on his Scooter and 3605 Ricky Racoon and his Scooter appear to be identical in every way but the set number. So why did Lego use two different numbers?
In some cases, there were different numbers for the USA and the rest of the world, but I don't know if that's the case with Ricky Racoon.

LEGO also extended from a 3-digit numbering to a 4-digit numbering around that time, so maybe some sets were renumbered. At the time, LEGO didn't seem to care that much about set numbers (and as you've noted, reused some).