Googling led me to this page where the author had the same problem, and they found a solution in Safari Bookmarks Extractor. I can't test that it still works with version changes in both, but it probably does. Once you have your extracted bookmarks, you just use Manage Bookmarks -> File -> Import -> From File.
I know I'm in the minority, but I enjoy using Netscape's browser ... Even after AOL got involved, I continued to surf with Netscape because that's what I've been using since college and (quite frankly) it's what I'm used to.