For this you need Ladik's MPQ Editor or something similar.
1. Navigate to where the MPQs are for the alpha (...\World of Warcraft Beta\Data)
2. Right click and copy expansion3.MPQ. Rename it to patch-1.MPQ
3. Inside of patch-1.MPQ, go to World\wmo\Dungeon\Skywall
4. Extract KL_Skywall_004.wmo to the desktop or somewhere you can find it at
5. Rename the extracted file to KL_Skywall_ENTRANCE.wmo
6. Add the renamed .wmo to patch-1.MPQ in the same location you extracted it from.
7. Make sure the patch-1.MPQ is in the same folder as all the other MPQs (...\World of Warcraft Beta\Data)
If you did everything right you should now be able to go around Uldum without crashing.
The command to go to Uldum is ".go 1 -9001 -1900 240".
I have uploaded the single file that is changed. All this needs to do is be placed in the ...\World of Warcraft Beta\Data folder.
http://www.mediafire.com/?mmmtjzl35mj