I'm posting this post from home and connecting via modem to my workstation using office internet connection without using any internet sharing program (a.k.a. winroute, wingate, freeproxy,...) and it works well! My connection speed is 33.6 Kb/s and works very fine! There is no need to make any special configuration from the dialer computer; just works like any normal internet ISP account!
Next test will cut through the IP routing so I'll be untraceable with a trace route software... wish me luck!