What are some alternatives?
When comparing jtrac and ZenDesk, you can also consider the following products
Jira - The #1 software development tool used by agile teams. Jira Software is built for every member of your software team to plan, track, and release great software.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
TeamClerk - Team Clerk is project and task management software that automatically keeps your team organized and monitors progress of all of your projects and tasks. Let us organize what you do,so you can focus on why you do it.
LiveAgent - LiveAgent is a fully-featured web-based live chat and helpdesk software. It harnesses the power of a universal inbox, real-time live chat, built-in call center, and a robust customer service portal. Start you free 14-day trial today.
Bugzilla - Bugzilla is a "Defect Tracking System" or "Bug-Tracking System".
HelpScout - Help Scout is a simple, straightforward way to provide excellent support