http://www.youtube.com/watch?v=_XEa-3eeedI ?
Maybe both were created around the same time? I know the Oracle was supposed to understand the human concept of choice and how we come by the decisions we make (probably how she "stumbled" upon the solution) but reading from that site that was mentioned in this thread I get the feeling that the different programs were also there to examine the different aspects of the human psyche (I think it was mentioned there that Persephone was to examine the concept of "love" while the Merv was supposed to examine the less savory aspects of humanity). I think maybe the reason why everyone would think the Oracle was older was because she is labeled as the "mother" of the Matrix. But it is possible she only garnered that moniker because she stumbled upon the solution (you know that could also explain the hatred the Merv has for the Oracle, I wouldn't be surprised if "jealousy" falls into the one of the many catagories the Merv was supposed to examine).