The seed itself I found on http://www.minecraftseeds.info
But we(on private server) found something that no one there seems to have found. (I commented there as well.)
There are villages at x:540 z:-280 and x:380 z:220 (so far that was known)
While exploring the caves under the village at 380 220 we eventually found ourselves at 630 340 in an abandoned mines system(under the ocean), that so far as I can tell holds about 10 spawners!!!!!!!(that we found so far)
Found 6 cave spiders, 2 skeleton, 2 spider spawners.
Turned on the checkpoints (rei's minimap) for the screenshot(The one called center is where we have our nether portal and safe room, there was a naturally generated room there already x:631 y:27 z:343):
Its XP farm heaven here....
(I've cleared out the area using buildcraft's filler machine, carefully avoiding the spawners)
Don't mind the trenches around the spawners, we were just marking the spawn range.
The location of the spawners varies a little each time I generated a new world but they were there every time.
Vanilla SSP 1.1:
Our double cave spider spawners were still there
and the ones in the main hall changed a bit but were still there also
and the ones in the main hall changed a bit but were still there also
Vanilla SSP 1.3.1:
There are the 4 spawners
And here we have the double spawner
And here we have the double spawner
EDIT: Added video:
Sorry about the quality had to record and encode on my laptop.
Video for 1.1 :
Video for 1.3.x:
EDIT: Decided to check this again on the newest minecraft version. They are still there even though the overworld generation changed the underground is still the same.
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