system freeze on kldload i4b

[J.L. te Linde]

Hi,

Previous FreeBSD-versions (2011, freebsd-7*)  worked fine with isdn4bsd: 
thanks !!
Using HFC-2BDS0 128K PCI ISDN adapter
The system was used as -headless- answering machine.

In 2014 , after updating to 9-series (just using a vanilla kernel), the 
system freezes when loading i4b
No debug info.

Yesterday , I've downloaded a fresh version of i4b (svn)
Clean compile!
(apart from some manpages decode.gz, file not found)
And again the system immediately freezes after kldload i4b.
No debug info.

FreeBSD 9.3-RELEASE-p24 #0: Sat Aug 22 01:54:44 UTC 2015

any ideas ?

kind regards,
sjonnie