MacOS X Snow Leopard / Cannot delete my old certifcate in keychain

I have imported a new iPhone Developer Cer开发者_如何学编程tificate in my keychain and deleted the old one since Xcode does not want to choose between two certificates when signing code (even when one is no more valid).

What's weird is that this old certificate sometimes shows up again whereas I already deleted it. So, I have to delete it several times a week.

Did someone face this issue ? Any idea to fix that ?

Many thanks, Franz

I answered a similar question here. I'm assuming you are using XCode 4, so your best bet is to follow my instructions for clearing out all your old stuff, and letting XCode do the legwork for you.

Switching to Xcode 4.2 (for Snow Leopard) solved the issue.