read-only buffer

[jirka . senkyr]

Hello.
In my emacs when I open a file which under a version control (SVN) the buffer 
is read-only. I do not want it. It's pretty annoying especially when using 
tags-query-replace. Then I need to make each buffer that opens by the 
tags-query-replace command writable by hitting C-x C-q. But by doing so 
tags-query-replace is terminated and I need to run it again and again and 
again....

I have searched emacs help and internet but haven't found a clue.

Does anybody know, how can I make emacs to open version controlled files in 
writable buffer?

Thanks,
Jiri