Apache load ballancing

[Przemyslaw Wegrzyn <czajnik@tower.t16.ds.pwr.wroc.pl>]

I need to build a scalable webserver based on Apache. I'm not sure yet if
the application requires persistent TCP connections. If so, it will
require that after starting session all subsequent HTTP request in this
session will come to the same machine in the cluster. This requires load
ballancing in 7th layer, so LVS doesn't help much. 

The question is: are there any software level 7 ballancer available ? If
not, which hardware box would you recommend ?

-=Czaj-nick=-