1
I've seen some XOOPS sites made integration with discuz forum
http://translate.google.com/translate?hl=en&sl=zh-CN&u=http://www.discuz.net/&sa=X&oi=translate&resnum=1&ct=result&prev=/search%3Fq%3Ddiscuz.net%26hl%3Den%26client%3Dfirefox-a%26channel%3Ds%26rls%3Dorg.mozilla:en-US:official%26hs%3D9Zi%26sa%3DG
like this one
http://www.5xue.com/modules/bbs/
where can i download the module
I Love Xoops