There exists a pidgin plugin for netsoul, its installation is made for BSDs, and not well documented for Linux. As we'll compile the plugin, we need to get pidgin sources, available in the pidgin-dev package:
$ sudo apt-get install pidgin-dev
Get a copy of the netsoul plugin, then just compile it without forgetting to redefine the ---prefix location:
$ tar -xf gaim-*.tar.gz $ cd gaim-netsoul-xxx $ ./configure --prefix=/usr $ make $ sudo make install