Tadd,
I've never heard of that issue before. Doing a quick search of Google, there's quite a few posts about JomSocial throwing that error. Most posts are pretty old though. The best description/solution I saw was
here
. Basically, it says it can be caused by a conflict between Mootools and jQuery. Your site is actually loading jQuery 4 different times with 2 different versions:
AdsManager and JomSocial - jQuery v1.6.2
jfbChat and your Bootstrap template - jQuery v1.7.1
My guess is the excessive loads of jQuery and the ordering of those being loaded with Mootools is an issue. My only quick suggestion is to try re-ordering the JFBCSystem plugin to the very top (lowest number) plugin. That will hopefully add Mootools before any of the 4 jQuery calls and help the problem.
If not, try disabling the JFBCSystem plugin altogether to see if the problem goes away.
If it does work without the JFBCSystem plugin, then re-enable it and try disabling adsmanaager, your template, or the jfbchat extensions to see if the problem goes away. We just need to narrow down where the conflict is coming from.
Hope that helps get you started and gives you some ideas.
Thanks,
Alex