I got it temporarly solved now, but just until a reboot...
I changed the following:
# Block TCP packets that do not mark the start of a connection
skip 2 in on [WAN Interface here] from [WAN SUBNET here] to any <--- i added this line
skip 1 in proto tcp all flags S/SAFR
block in $log quick proto tcp all <--- this was the rule wich blocked the redirect?!?!
Now can please help me someone to mount that ufs image? I want to change it permanently.
I already tried to mount the image on linux with
mount imagefile /mnt/tmp -o loop
I have compiled the ufs kernel module before and the mount command works now, but i can't see any