Subversion doesn't store credentials in kwallet

Greetings.

I'm experiencing a problem with using KWallet as a password store. My
operating system is openSUSE 13.2 (x86_64) and I can reproduce the issue
with the Subversion 1.8.11 (r1643975) binaries provided by openSUSE, as
well as Subversion 1.9.0-beta1 compiled from source (configured only with
--libdir=/usr/local/lib64 and no other options, and built with GCC 4.8.3).

In my ~/.subversion/config I have KWallet storage enabled with the
following lines:

[auth]
password-stores = kwallet

Despite this, when I try to check out or commit files with a password-
protected repository, Subversion doesn't invoke KWallet to fetch or store
credentials:

> $ svn co https://www.example.com/svn/foo
> Authentication realm: <https://www.example.com:443> Foobar Domain Login
> Password for 'bar': ********
>
>
> -----------------------------------------------------------------------
>
> ATTENTION! Your password for authentication realm:
> <https://www.example.com:443> Foobar Domain Login
>
> can only be stored to disk unencrypted! You are advised to configure
> your system so that Subversion can store passwords encrypted, if
> possible. See the documentation for details.
>
> You can avoid future appearances of this warning by setting the value
> of the 'store-plaintext-passwords' option to either 'yes' or 'no' in
> '/home/bar/.subversion/servers'.
> -----------------------------------------------------------------------
> Store password unencrypted (yes/no)?

Any idea what could be wrong here? Other applications on my system don't
have any problem using KWallet. And I wasn't having this problem a few
months ago, so I'm assuming something broke after an upgrade of Subversion
and/or KWallet.

I see someone else has already opened an issue for this at
<http://subversion.tigris.org/issues/show_bug.cgi?id=3595> but it's been
closed due to their not having first posted the issue here.

Regards,
Tristan

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