Hi lembit!
Yes, that's a straight forward task if you already familiar with the Joomla framework, otherwise it can be a nightmare!
It looks like your application has been designed and implemented using Perl/MySQL, right?
If yes, what you'll need is to translate your application to the Joomla 1.5 framework.
I would start that task by the following:
1. Setup your environment;
2. Register you new component in the database;
3. Structure and develop you back end (if needed);
4. Structure and develop you front end;
5. Test you new component;
Before doing that you will need to learn at least the basics of the MVC design pattern. This will help you to develop you component using the correct structure, classes, etc.
It might sounds a bit scary but instead is very interesting and helpful, if you have already some software development experience really and take it serious, you'll be able to learn in a couple of days!
Find below some links to help your research:
dev.joomla.org/content/view/1137/80/
dev.joomla.org/component/option,com_jd-w...ts:hello_world_mvc1/
Let me know if you need a hand!
Cheers,
Jose Soares