Hello again,
I was able to recover all deleted partitions :)
I found this program http://ls.si.ru/freebsd/find-super-blocks.c
it provides me sufficient information for recreating both
partitions.
From another FreeBSD machine it was as easy as:
prue5# ./find-super-blocks /dev/ad2s2
FS_MAGIC at
Hello,
I was trying to install FreeBSD 5.2 in the slice ad0s3 but
accidentally I wiped two partitions of my 4.9 system which
were in the ad0s2 slice :(
ad0s1 - Linux boot
ad0s2 - FreeBSD 4.9 (deleted partitions)
ad0s3 - FreeBSD 5.2
ad0s4 - Extended partition
they were the root and var