This is a fix for the Quake BSP eXpansion Level PAK #1. 
http://www.vvm.com/~fishman/quake/

copy these 2 replacement leves into your id1/maps dir and overwrite 
the previos versions of these levels.

The problem was that whenever 1bsp4 would try to start on quakeworld then
it would lock up, and on 1bsp9 there was a spot that you could get trapped in 
the water...only on quakeworld though...all this fix does is makes the 
exit flag for 1bsp3 set to 1bsp5..so actually there is only 9 levels now. =(

if you find anymore problems then please email fishman@vvm.com
thanks and sorry for the inconvience