5 is too low for ktorrent socket queue. Much more peers can connect at once.
Why system default not used?
George why use 5 in ( libbtcore/net/socket.cpp:203 ) ? Favorite number? ))

Ktorrent produce many network errors:
netstat -s
...
7545 times the listen queue of a socket overflowed

Also kernel print warnings about syn flooding ))

I have no special attachment to the number 5, it's just some value which got put there the first time that code was written (a long time ago), haven't got a clue why, probably didn't think about it much.

Will change it to SOMAXCONN, which seems to be 128 on linux.