Cannot authenticate via IndieAuth

[NicoleRauch]

I've set up my website http://nicole-rauch.de to act as an OpenID authentication provider; it delegates to IndieAuth.com to perform the actual authentication.

When I use this to authenticate myself at https://www.softwerkskammer.org (which uses passport-openid ver 0.3.1), I'm taken to IndieAuth and I can authenticate there; but on return I get the following error message:

Failed to verify assertion (message: No valid providers were discovered for the asserted claimed identifier)
at /home/swk/plattform/node_modules/passport-openid/lib/passport-openid/strategy.js:184:36
at /home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1069:12
at _verifyAssertionAgainstProviders (/home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1212:3)
at /home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1137:14
at openid.loadDiscoveredInformation (/home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:134:10)
at pass (/home/swk/plattform/node_modules/passport-openid/lib/passport-openid/index.js:77:14)
at Object.openid.loadDiscoveredInformation (/home/swk/plattform/node_modules/passport-openid/lib/passport-openid/index.js:85:5)
at _verifyDiscoveredInformation (/home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1128:10)
at _verifyAssertionData (/home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1067:3)
at Object.openid.verifyAssertion (/home/swk/plattform/node_modules/passport-openid/node_modules/openid/openid.js:1052:10)

The URL that is being passed to this._relyingParty.verifyAssertion() is this one:

/openid/callback?openid.assoc_handle=%7BHMAC-SHA1%7D%7B54a95396%7D%7BVXl4iQ%3D%3D%7D&openid.identity=http%3A%2F%2Fnicole-rauch.de%2F&openid.mode=id_res&openid.op_endpoint=https%3A%2F%2Findieauth.com%2Fopenid&openid.response_nonce=2015-01-04T14%3A52%3A30ZJ7xAWH&openid.return_to=http%3A%2F%2Flocalhost%3A17124%2Fauth%2Fopenid%2Fcallback&openid.sig=hGeEoQg9KJkpUhqsf334wDhlRNg%3D&openid.signed=assoc_handle%2Cidentity%2Cmode%2Cop_endpoint%2Cresponse_nonce%2Creturn_to%2Csigned

Do you have any idea of what might be going wrong here?

Thanks for your help! -- Nicole.