I will update that information to say it requires mojoPortal 18.104.22.168, sorry for any inconvenience.
Sorry for the inconvenience. I was worried about breaking other people's custom code by updating to the new log4net because I thought it might require everyone to re-compile their custom features against the new log4net dll, but I was able to prevent that problem by adding this in the Web.config in 22.214.171.124:
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
<bindingRedirect oldVersion="126.96.36.199-188.8.131.52" newVersion="184.108.40.206" />
though it still would be best for anyone using custom code that also uses log4net to re-reference it and re-compile when they get a chance.