diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3f0bd151..acdd5953 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 ### Updated
 - English translation for "Feels" to "Feels like"
 - Fixed the example calender url in `config.js.sample`
+- Update `ical.js` to solve various calendar issues.
 
 ### Fixed
 - Handle SIGTERM messages
diff --git a/modules/default/calendar/vendor/ical.js/ical.js b/modules/default/calendar/vendor/ical.js/ical.js
index 8f0c532b..024625b7 100644
--- a/modules/default/calendar/vendor/ical.js/ical.js
+++ b/modules/default/calendar/vendor/ical.js/ical.js
@@ -33,9 +33,9 @@
     for (var i = 0; i<p.length; i++){
       if (p[i].indexOf('=') > -1){
         var segs = p[i].split('=');
-        
+
         out[segs[0]] = parseValue(segs.slice(1).join('='));
-        
+
       }
     }
     return out || sp
@@ -44,7 +44,7 @@
   var parseValue = function(val){
     if ('TRUE' === val)
       return true;
-    
+
     if ('FALSE' === val)
       return false;
 
@@ -55,75 +55,52 @@
     return val;
   }
 
-  var storeParam = function(name){
-    return function(val, params, curr){
-      var data;
-      if (params && params.length && !(params.length==1 && params[0]==='CHARSET=utf-8')){
-        data = {params:parseParams(params), val:text(val)}
-      }
-      else
-        data = text(val)
+  var storeValParam = function (name) {
+      return function (val, curr) {
+          var current = curr[name];
+          if (Array.isArray(current)) {
+              current.push(val);
+              return curr;
+          }
 
-      var current = curr[name];
-      if (Array.isArray(current)){
-        current.push(data);
-        return curr;
-      }
+          if (current != null) {
+              curr[name] = [current, val];
+              return curr;
+          }
 
-      if (current != null){
-        curr[name] = [current, data];
-        return curr;
+          curr[name] = val;
+          return curr
       }
-
-      curr[name] = data;
-      return curr
-    }
   }
 
-  var addTZ = function(dt, params){
+  var storeParam = function (name) {
+      return function (val, params, curr) {
+          var data;
+          if (params && params.length && !(params.length == 1 && params[0] === 'CHARSET=utf-8')) {
+              data = { params: parseParams(params), val: text(val) }
+          }
+          else
+              data = text(val)
+
+          return storeValParam(name)(data, curr);
+      }
+  }
+
+  var addTZ = function (dt, params) {
     var p = parseParams(params);
 
-    if (params && p && dt){
+    if (params && p){
       dt.tz = p.TZID
     }
 
     return dt
   }
 
-  var parseTimestamp = function(val){
-    //typical RFC date-time format
-    var comps = /^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(Z)?$/.exec(val);
-    if (comps !== null) {
-      if (comps[7] == 'Z'){ // GMT
-        return new Date(Date.UTC(
-          parseInt(comps[1], 10),
-          parseInt(comps[2], 10)-1,
-          parseInt(comps[3], 10),
-          parseInt(comps[4], 10),
-          parseInt(comps[5], 10),
-          parseInt(comps[6], 10 )
-        ));
-        // TODO add tz
-      } else {
-        return new Date(
-          parseInt(comps[1], 10),
-          parseInt(comps[2], 10)-1,
-          parseInt(comps[3], 10),
-          parseInt(comps[4], 10),
-          parseInt(comps[5], 10),
-          parseInt(comps[6], 10)
-        );
-      }
-    }
-
-    return undefined;
-  }
-
   var dateParam = function(name){
-    return function(val, params, curr){
+      return function (val, params, curr) {
+
+      var newDate = text(val);
 
-      // Store as string - worst case scenario
-      storeParam(name)(val, undefined, curr)
 
       if (params && params[0] === "VALUE=DATE") {
         // Just Date
@@ -131,47 +108,54 @@
         var comps = /^(\d{4})(\d{2})(\d{2})$/.exec(val);
         if (comps !== null) {
           // No TZ info - assume same timezone as this computer
-          curr[name] = new Date(
+          newDate = new Date(
             comps[1],
             parseInt(comps[2], 10)-1,
             comps[3]
           );
 
-          curr[name] = addTZ(curr[name], params);
-	  return curr;
+          newDate = addTZ(newDate, params);
+          newDate.dateOnly = true;
+
+          // Store as string - worst case scenario
+          return storeValParam(name)(newDate, curr)
         }
       }
 
-      curr[name] = []
-      val.split(',').forEach(function(val){
-        var newDate = parseTimestamp(val);
-        curr[name].push(addTZ(newDate, params));
-      });
 
-      if (curr[name].length === 0){
-        delete curr[name];
-      } else if (curr[name].length === 1){
-	 curr[name] = curr[name][0];
-      }
+      //typical RFC date-time format
+      var comps = /^(\d{4})(\d{2})(\d{2})T(\d{2})(\d{2})(\d{2})(Z)?$/.exec(val);
+      if (comps !== null) {
+        if (comps[7] == 'Z'){ // GMT
+          newDate = new Date(Date.UTC(
+            parseInt(comps[1], 10),
+            parseInt(comps[2], 10)-1,
+            parseInt(comps[3], 10),
+            parseInt(comps[4], 10),
+            parseInt(comps[5], 10),
+            parseInt(comps[6], 10 )
+          ));
+          // TODO add tz
+        } else {
+          newDate = new Date(
+            parseInt(comps[1], 10),
+            parseInt(comps[2], 10)-1,
+            parseInt(comps[3], 10),
+            parseInt(comps[4], 10),
+            parseInt(comps[5], 10),
+            parseInt(comps[6], 10)
+          );
+        }
 
-      return curr;
+        newDate = addTZ(newDate, params);
     }
+
+
+          // Store as string - worst case scenario
+      return storeValParam(name)(newDate, curr)
+      }
   }
 
-  var exdateParam = function(name){
-    return function(val, params, curr){
-      var date = dateParam(name)(val, params, curr);
-      if (date.exdates === undefined) {
-        date.exdates = [];
-      }
-      if (Array.isArray(date.exdate)){
-        date.exdates = date.exdates.concat(date.exdate);
-      } else {
-        date.exdates.push(date.exdate);
-      }
-      return date;
-    }
-  }
 
   var geoParam = function(name){
     return function(val, params, curr){
@@ -195,7 +179,52 @@
     }
   }
 
-  var addFBType = function(fb, params){
+  // EXDATE is an entry that represents exceptions to a recurrence rule (ex: "repeat every day except on 7/4").
+  // The EXDATE entry itself can also contain a comma-separated list, so we make sure to parse each date out separately.
+  // There can also be more than one EXDATE entries in a calendar record.
+  // Since there can be multiple dates, we create an array of them.  The index into the array is the ISO string of the date itself, for ease of use.
+  // i.e. You can check if ((curr.exdate != undefined) && (curr.exdate[date iso string] != undefined)) to see if a date is an exception.
+  // NOTE: This specifically uses date only, and not time.  This is to avoid a few problems:
+  //    1. The ISO string with time wouldn't work for "floating dates" (dates without timezones).
+  //       ex: "20171225T060000" - this is supposed to mean 6 AM in whatever timezone you're currently in
+  //    2. Daylight savings time potentially affects the time you would need to look up
+  //    3. Some EXDATE entries in the wild seem to have times different from the recurrence rule, but are still excluded by calendar programs.  Not sure how or why.
+  //       These would fail any sort of sane time lookup, because the time literally doesn't match the event.  So we'll ignore time and just use date.
+  //       ex: DTSTART:20170814T140000Z
+  //             RRULE:FREQ=WEEKLY;WKST=SU;INTERVAL=2;BYDAY=MO,TU
+  //             EXDATE:20171219T060000
+  //       Even though "T060000" doesn't match or overlap "T1400000Z", it's still supposed to be excluded?  Odd. :(
+  // TODO: See if this causes any problems with events that recur multiple times a day.
+  var exdateParam = function (name) {
+    return function (val, params, curr) {
+      var separatorPattern = /\s*,\s*/g;
+      curr[name] = curr[name] || [];
+      var dates = val ? val.split(separatorPattern) : [];
+      dates.forEach(function (entry) {
+          var exdate = new Array();
+          dateParam(name)(entry, params, exdate);
+
+          if (exdate[name])
+          {
+            if (typeof exdate[name].toISOString === 'function') {
+              curr[name][exdate[name].toISOString().substring(0, 10)] = exdate[name];
+            } else {
+              console.error("No toISOString function in exdate[name]", exdate[name]);
+            }
+          }
+        }
+      )
+      return curr;
+    }
+  }
+
+  // RECURRENCE-ID is the ID of a specific recurrence within a recurrence rule.
+  // TODO:  It's also possible for it to have a range, like "THISANDPRIOR", "THISANDFUTURE".  This isn't currently handled.
+  var recurrenceParam = function (name) {
+      return dateParam(name);
+  }
+
+  var addFBType = function (fb, params) {
     var p = parseParams(params);
 
     if (params && p){
@@ -239,7 +268,7 @@
             //scan all high level object in curr and drop all strings
             var key,
                 obj;
-            
+
             for (key in curr) {
                 if(curr.hasOwnProperty(key)) {
                    obj = curr[key];
@@ -248,14 +277,93 @@
                    }
                 }
             }
-            
+
             return curr
         }
-        
+
         var par = stack.pop()
 
         if (curr.uid)
-          par[curr.uid] = curr
+        {
+        	// If this is the first time we run into this UID, just save it.
+        	if (par[curr.uid] === undefined)
+            {
+            	par[curr.uid] = curr;
+            }
+            else
+            {
+                // If we have multiple ical entries with the same UID, it's either going to be a
+                // modification to a recurrence (RECURRENCE-ID), and/or a significant modification
+                // to the entry (SEQUENCE).
+
+                // TODO: Look into proper sequence logic.
+
+                if (curr.recurrenceid === undefined)
+                {
+                    // If we have the same UID as an existing record, and it *isn't* a specific recurrence ID,
+                    // not quite sure what the correct behaviour should be.  For now, just take the new information
+                    // and merge it with the old record by overwriting only the fields that appear in the new record.
+                    var key;
+                    for (key in curr) {
+                    	par[curr.uid][key] = curr[key];
+                    }
+
+                }
+            }
+
+        	// If we have recurrence-id entries, list them as an array of recurrences keyed off of recurrence-id.
+        	// To use - as you're running through the dates of an rrule, you can try looking it up in the recurrences
+        	// array.  If it exists, then use the data from the calendar object in the recurrence instead of the parent
+        	// for that day.
+
+        	// NOTE:  Sometimes the RECURRENCE-ID record will show up *before* the record with the RRULE entry.  In that
+        	// case, what happens is that the RECURRENCE-ID record ends up becoming both the parent record and an entry
+        	// in the recurrences array, and then when we process the RRULE entry later it overwrites the appropriate
+			// fields in the parent record.
+
+        	if (curr.recurrenceid != null)
+        	{
+
+        		// TODO:  Is there ever a case where we have to worry about overwriting an existing entry here?
+
+        		// Create a copy of the current object to save in our recurrences array.  (We *could* just do par = curr,
+        		// except for the case that we get the RECURRENCE-ID record before the RRULE record.  In that case, we
+        		// would end up with a shared reference that would cause us to overwrite *both* records at the point
+				// that we try and fix up the parent record.)
+        		var recurrenceObj = new Object();
+        		var key;
+        		for (key in curr) {
+        			recurrenceObj[key] = curr[key];
+        		}
+
+        		if (recurrenceObj.recurrences != undefined) {
+        			delete recurrenceObj.recurrences;
+        		}
+
+
+				// If we don't have an array to store recurrences in yet, create it.
+        		if (par[curr.uid].recurrences === undefined) {
+        			par[curr.uid].recurrences = new Array();
+            	}
+
+        		// Save off our cloned recurrence object into the array, keyed by date but not time.
+        		// We key by date only to avoid timezone and "floating time" problems (where the time isn't associated with a timezone).
+				// TODO: See if this causes a problem with events that have multiple recurrences per day.
+                if (typeof curr.recurrenceid.toISOString === 'function') {
+                  par[curr.uid].recurrences[curr.recurrenceid.toISOString().substring(0,10)] = recurrenceObj;
+                } else {
+                  console.error("No toISOString function in curr.recurrenceid", curr.recurrenceid);
+                }
+            }
+
+        	// One more specific fix - in the case that an RRULE entry shows up after a RECURRENCE-ID entry,
+        	// let's make sure to clear the recurrenceid off the parent field.
+        	if ((par[curr.uid].rrule != undefined) && (par[curr.uid].recurrenceid != undefined))
+            {
+        		delete par[curr.uid].recurrenceid;
+            }
+
+        }
         else
           par[Math.random()*100000] = curr  // Randomly assign ID : TODO - use true GUID
 
@@ -277,6 +385,11 @@
       , 'COMPLETED': dateParam('completed')
       , 'CATEGORIES': categoriesParam('categories')
       , 'FREEBUSY': freebusyParam('freebusy')
+      , 'DTSTAMP': dateParam('dtstamp')
+      , 'CREATED': dateParam('created')
+      , 'LAST-MODIFIED': dateParam('lastmodified')
+      , 'RECURRENCE-ID': recurrenceParam('recurrenceid')
+
     },
 
 
@@ -292,7 +405,7 @@
           name = name.substring(2);
           return (storeParam(name))(val, params, ctx, stack, line);
       }
-      
+
       return storeParam(name.toLowerCase())(val, params, ctx);
     },