Unselectable text in GtkTextView

[Or Goshen <oberon netvision net il>]

Hello

Is there a way to make a tag in GtkTextView unselectable ?
So the user wont be able to select it while dragging the mouse , only the text surrounding it ?
I wonna create a new widget and GtkTextView will be it's parent , the unselectable text is a feature i need to implement .
Setting a GtkTextTag uneditable is easy ( there is a property for that ) , but how do you make it unselectable ?

to make it clear I'll show you what I mean , this is how the widget should look after the user added some text ( the numbering were added automaticly by the widget ) :
http://t2.technion.ac.il/~soberon/widget1.jpg

This is how it should look after the user dragged/selected the whole text ( notice the numbering werent selected ) :
http://t2.technion.ac.il/~soberon/widget2.jpg

I guess if there was a property in GtkTextTag that enables you to choose whether or not text can be selected, so a code line such as this would be possible :
gtk_text_buffer_create_tag (buffer, "selectable",
                              "selectable", TRUE, NULL);
# from gtk-demo->text widget
,would be the easiest thing.

 I do not want to suggest a new api ( I think it would take too long to code this ) , I just wanna know if there is a way to do than with current code .