Update 2012-02-07: I didn’t know about Open-SUSE’s 1-Click Install when I first installed Keepassx and wrote the post below. The simplest solution turned out to be searching on http://software.opensuse.org/ for Keepassx, and then click 1-Click Install. Easy! (still had to accept the security key though).
I recently switched to openSUSE on my T61 laptop, but then found I couldn’t install KeepassX because wasn’t available in the default repositories. Here’s how I solved that:
1) Open YAST and, under the Software category, open User and Group Management.
2) Click Add and add repository http://download.opensuse.org/repositories/security:/passwordmanagement/openSUSE_11.4/
YAST reported that the encryption key for the repository had expired and reported I could accept it, but I had to expand the window first before I could see the Accept button.
3) Open Install/Remove Software, search for KeepassX and install.