iBrowser plugin for TinyMCE: how to change IMG tag insert code

Question

Hello, World!

I've got iBrowser plugin and what i need is to change HTML code for the img tag when I click insert button. Actually i want to have the opportunity to insert alternative code (user could check a certain checkbox, or click another button, say "Insert link" next to "insert").

Now the code looks like this

<img title="xxx" src="path/to/thumb.jpg" alt="xxx" width="yyy" height="nnn">

So, the question is: where could i find the location of insert button, to add another one next to it. And where can i write code to insert my custom html code?

Thanks