Cannot get rid of a link in a text view

Serious problem:

My application “Panel 1.0” uses a text view to hold the content. If you start the application and drag and drop a link from Safari into it directly, the link appears.

If you then delete the link and type some text, that text remains linked to the url the link had before and appears as linktext.

There is no way to get rid of it except restarting the application.

Most interesting: If you first type a space in the text view before pasting a link, you may type a space after the link followed by text and this text will not be linked.

Confusing!

Does anyone know (maybe by a call method) how to reset a text view to it’s default state?

Thanks in advance!
Thomas