Sometime back, I got a task to integrate calendar in one of the web applications that I was working on. I checked out a whole bunch of options and finally settled on Full Calendar jQuery plugin, for doing the job. Full Calendar plugin is a free plugin, but, this plugin has all the features and an exhaustive documentation that can give all the paid plugins run for their money.
The jQuery plugin was working smoothly in all the browsers, until, I tested it on IE 8. I checked their support page and read that Full Calendar plugin was indeed compatible with IE 8 and their team had tested it, but, the jquery version mentioned was less than 2.0.x. I replaced the jQuery version 2.1.1 present in the lib folder of the plugin with jQuery version 1.11.1 and the plugin worked smoothly in IE 8 for me.
The jquery.min.js which was present in lib folder of the plugin had version was 2.1.1. If you are facing the same problem, then, I will suggest you to use jQuery version below 2.0.x.