software equivalent in linux
 

i wonder if there is any porting or equivalent or substitution for winmx in linux platform.

There is an open source file sharing application for linux available from gift.sf.net, this can connect through plugins to it's own p2p network (openFT) gnutella, and fasttrack (kazaa's p2p network) and there maybe support for winmx.

There is also 2 clients for soulseek (http://www.slsknet.org) p2p network called pyslsk (http://www.sensi.org/~ak/pyslsk/) which I personally use, and nicotine (http://nicotine.thegraveyard.org/) which is prettier.