See attached my latest version for /usr/lib/obex/obexd on the N900.

In this version:
1. vcards are properly separated by CR/LF
2. multiple (TEL) entries are included in the vcards
3. only entries the client (carkit) asks for are returned

Note that this version only differs from the earlier workaround version by solving problem 3.

One issue remains: my carkit (Peugeot Connect Nav) lists every contact twice. Anyone with the same problem?

I found my carkit asks for two different phonebooks: SIM1/telecom/pb and telecom/pb. The N900 (with the ebook backend) sends the same contacts for both requests, leading to duplicate contacts.