[strongSwan] Problem exporting pkcs12-File

[Stefan Malte Schumacher]

Dear members of the strongSwan-Community

I am trying to create an encrypted connection between my home server
"Mars" and my laptop "Deimos". I have created a CA as well as keys and
certificates for each of my peers according to the instruction at
http://wiki.strongswan.org/projects/strongswan/wiki/SimpleCA. Now I
want to create the necessary pk12-file which I can import in Windows 7
on "Deimos".  According to my information the necessary command should
be as follows: "openssl pkcs12 -export -inkey deimosKey.der -in
deimosCert.der -name "Deimos" -certfile caCert.der -caname "Stefan
Malte Schumacher CA" -out deimos.p12". Unfortunately I only get an
error message "unable to load private key" despite the fact that the
deimosKey.der is containted in the current working directory. What am
I doing wrong?

Sincerely
Stefan Malte Schumacher