Ocelots spawn using the hostile mob spawning system. This causes the following behaviours:
They spawn only a certain distance to the players (like hostile mobs)
They quickly despawn if you are leaving the area
They don't spawn on peaceful making in impossible to gets cats in peaceful mode.
They don't spawn on servers with spawn-monsters=false in the server.properties making it impossible to get cats on such servers (without cheating spawn eggs).
Neither of these behaviours make really sense as ocelots are (currently) not hostile. Ocelots should spawn using the same method, wolves, cows, etc. spawn so they can still be found in peaceful mode. The current behaviour irritates a lot of users who are wondering why they find no ocelots while playing on a peaceful map. (google "no ocelot spawning minecraft" or similar for examples)
Linked issues
duplicates 1
Comments 4
This has been intentionally filed as new bug, because
1) MC-1788 only handles peaceful mode and not the other aspects
2) The "Works As Intended" solution applies according to http://www.minecraftwiki.net/wiki/Issues/Weekly_12w04a#Bugs_7 only to the despawning behaviour and not to the whole package of unintended behaviour. Especially Jeb never stated that it's intended for ocelots not to be available in peaceful mode, probably because that would be just stupid. Otherwise please explain how it can be intended that peaceful mobs spawn using the hostile spawner. This is clearly a bug. Peaceful mobs should spawn using the peaceful spawner obviously.
Ok, first you quote is out of context. The bug entry is "Ocelots despawn." There is no evidence Jeb even realized that spawning ocelots using the hostile mob spawner causes them to not appear in peaceful mode.
Secondly, this entry is more than a year old. There have been huge changes in the Minecraft code relating to mob spawning, for example making peaceful mobs more persistent etc. A year ago, spawning ocelots using the hostile spawner didn't make much of a difference, but it now does.
At least this issue should be brought to Mojangs attention, and if they still believe it's intentionally this way, I'm fine with that, but I doubt it.
Duplicate of MC-1788, please use the search function to see if your bug has already been submitted. Currently over 55% of tickets are being closed as duplicate.