I've encountered following problem while using Opera web browser:

When I click on a magnet link on some web page like

magnet:?xt=urn:tree:tiger:CXW6MJFRNOEFU2STCBWWOIYZLVCR2FTR37SQCXY&xl=352342016&dn=ER%20-%207x16%20-%20Witch%20Hunt.avi 

Opera is asking me if I want to open that link with my DC++ client.

If I click 'Yes' button then my DC++ client is correctly "opening" the clicked magnet link and performing some action on it. There is also an option "Do not show this dialog again" in Opera's dialog, but it doesn't seem to be working correctly. If I check that option before answering 'Yes' and then click on other magnet link of the same kind the Opera will again ask me about how to open new link.

I haven't found protocol association in 'Control Panel > Default Programs > Set Associations' part of my Windows Vista settings, but if I paste magnet link in "Run" dialog then Vista will handle that link perfectly.

I've tried to find out how to manually set protocol association in Opera and found 'Programs' page of browser's advanced settings. There I discovered that instead of storing protocol to application associations Opera tries to store per-link associations (There are several entries with exact links as they was on web page as value of protocol field). If I click on the links which are already stored in Opera's protocols associations browser will ask me about them again.

I haven't found any information on how to resolve this problem on the internet, maybe someone on this site will be able to help me.