Pre-programmed pokemon?

[Tsujin]

Does anyone know if the roaming pokemon in HG/SS are pre-programmed with certain IV's and natues once they start roaming? I don't believe they are but today I attempted to catch my Latios and just SR for a Timid or Modest nature with decent IV's but the first time I caught it, it was Brave with some crappy IV's. however the second time I caught it, it had the same nature and the EXACT same IV's, the third time was the EXACT same. So it would be really helpful if someone could answer this for me so I don't attempt to get a different nature again.

[Bitoko4]

Yes, unfortunately as soon as they start roaming, they have the same Nature/IV's

[Tsujin]

Yes, unfortunately as soon as they start roaming, they have the same Nature/IV's

Agh!! That sucks majorly... It took me forever too to hunt him down and catch him 3 times and now I still have to do it again. Thanks for the info though.

[Bitoko4]

Yeah, I was sorely dissapointed when my Raikou had an Impish nature and horible IV's.

[War]

Yeah, I was sorely dissapointed when my Raikou had an Impish nature and horible IV's.

All my Legendaries have Natures that work AGAINST their best stats!!!! WTF!