Bug#384038: kwalletmanager not populating passwords
I had this same problem for a while. In my case the problem was that I
accidently denied konqueror kwallet access. Konqueror would continue
to ask to save the passwords, but kwallet would reject the
operation. However, neither kwallet nor konqueror would notify me of
that the request had been rejected.
To see if this is what happened to you:
1) Open kwalletmanager
2) Go to: Settings->Configure Wallet->Access Control
3) expand the kdewallet treeview and see if the konqueror policy is
set to deny always.