Topics -> Calendar -> Bug

getting this error on all "topic"-Sites, not on the main-page:

[HopMacro error in site.calendar: org.mozilla.javascript.EvaluatorException: Cannot convert NaN to java.lang.Integer (site/macros.js; line 393)]

same problem in many other antville-logs - you can test it here: help.antville.org

seems to be a bug ?