Has anyone managed to play a 2 player match via DOSBox or Gog.com installation?
In the old days you could "trick" the game into working in 2 player mode by using 2 mice with 2 different mouse drivers.
According to a thread on the DOSBox forums (http://vogons.zetafleet.com/viewtopic.php?t=17989) it should be possible using a Serial/COM1 mouse. Has anyone tried this out?

I think the game, in addition to split-screen multiplay, has only modem and null modem cable multiplay modes.
Iirc DOSBox only has support for IPX mode multiplay.

DOSBox supports more than you think ;)

So, does this mean Settlers 2 multiplayer works?

Have a look at Return to the Roots. It provides a good multiplayer capability, although it is still under development so you shouldn't expect everything to work perfectly. But as far as I know it is playable.