Ok, fixed the problem.
I couldn't find kwallet under YaST as it was bundled in another package called kdeutils3:
and it turns out it was already installed. It just didn't appear on my desktop tray.
It appears on my tray if I typed from a shell:
after that, it was a simple matter of following the instructions under
* Right click wall icon in tray
* Select "Configure Wallet"
* Check "Enable the KDE wallet subsystem" on the tab "Wallet Preferences"
if you disconnected/reconnected your network connection with SSID, kwallet would kick in and prompt you for a password, and subsequently save your SSIDs. Then any subsequent reconnection will be automatic.