i can feel your pain! and fireside brings up an important point – intellectual property. that means that your application goes beyond the source code you’ve written and the physical files and database it maintains.
your company owns the ideas that led to the realization of your time management system. that includes the designs (architectural, logical and physical DB, detailed design, code base, and on and on it goes) of your application.
So, even if you were to rewrite your application in a different language using a different file system and DBMS, if the completely rewritten application implements the same designs, guess what – you’ve still “stolen” the IP of your company’s time management system, that is the designs belong to the company and you can’t, essentially, recreate the same wheel!
your wheel needs to be different. and if you think about it, there are probably things you would have done differently given what you learned about the problem domain. perhaps you know certain aspects of your design that don’t perform well – architectural features that don’t perform well, redundancies, missing features/functions..those sorts of things. aspects that aren’t scalable. maybe your new wheel should be n-tiered.
young developers tend to be purists – i know i was. that usually leaves room for implementing say a pentagonal application that functions in a specific setting better than the original wheel.
and dog’s advice is right on. if you ever have an idea that you believe is an original and winning marketable idea, keep it to yourself – don’t even ask for an opinion about the idea at your job. although there are cases where a former employee won against his employer because he implemented an idea his employer completely and totally rejected, you’re taking you chances if you think you have a marketable idea.
best of luck to you in your career – and live and learn!