I have been using xchat for years, but lately it hangs all the time ( i'm using silverex.org builds ). So i need a temporary alternative. Something with multiple server support.
Oh .. and no , i won't use mirc.
Perhaps IRC Clients for Windows would be of interest to you.
Miranda IM and Pidgin support IRC, and multiple IRC servers, in addition to IM services. I haven't used MirandaIM's support for a while, but Pidgin was lacking in scriptability.
HydraIRC would be my choice, easy to use, free open source and portable.
try xchat-wdk, it provides fresh builds of xchat svn. runs stable for me (windows 7 x64).