ZEBRA/OSPF and HDLC

Hi!

Running a network with several Ethernet-connections with zebra-boxes,
a little problem occured when we started using serial Links with
Cyclades-Cards and HDLC-Interfaces within our internal Backbone:

Configuring the hdlc-Interfaces as point-to-point I can't see any
OSPF-Traffic on this link.

Configuring the hdlc-Interfaces like that:
ip addr add 10.10.5.242/29 dev hdlc1
ifconfig hdlc1 arp multicast promisc up
the OSPF-Link becomes established (sh ip ospf nei)
10.10.11.233 1 Full/DR 00:00:37 10.10.5.241 \
hdlc1:10.10.5.242 1 0 0
but unfortunately there is no corresponding routing-entry (sh ip osp rou)
to hdlc1 (OSPF network routing table)

So how to configure an OSPF-Link via HDLC-Lines with zebra?