According to the jquery page, here is the complete list of chars that need quoting: #;&,.+*~':"!^$[]()=>|/

So clearly there's a few more that need adding 🙂

Also, rather than adding a series of replace calls, it could be written: sid.replace(/([\#\;\&\,\.\+\*\~\'\:\"\!\^\$\[\]\(\)\=\>\|\/])/g,"\\$1");

Or maybe just quote everything but the “usual selector chars”: sid.replace(/([^-a-zA-Z_0-9])/g, “\\$1”);