How to uninstall Modelsim-Altera from Ubuntu 10.10?

I erroneously downloaded and installed the licensed version of Modelsim-Altera on Ubuntu. It came in as a .sh file.

Now I am re-downloading the starter edition of Modelsim-Altera that doesn't require a license. However prior to that I would like to uninstall the old version. I don't have a clue how to do that on Ubuntu.

Could anyone help out?