well, that is strange,
i tested that. its true, i get more connection ...

but i also see ofen this :
"Warning: LOST CONTACT WITH BITCOIND for" is displayed ... perhaps these linux bash box dont runs cleanly.
it fells like it freeze every few minutes:

and after restart now in bench mode (i also put in new tcp rule for in- and outgoing tcp connection on port 9332 and 9333) :
without miner connected : www.c-xantus.de/log4
with miner connected : www.c-xantus.de/log5

by the way, P2Pool is using at linux bash with pypy 1,3Gb Memory an betwen 0 and 15% cpu