missing libncurses.so.5 and other lib*

hi,

not a freebsd bug, rather a blackout in my head. therefore not clear 
where the appropriate mailing list is.
done a portupgrade via cvsup. fine.
used portsclean with the -iL ( or -iD) switch, to clean out unused
shared libraries. 
and now I blew it up:
with the message: /usr/lib/libcurses.so.5  is shadowed by .... etc.
and other messages, all concerning lib** . I deleted them all.
now I remember installing compat-4-* a short time before as
/ports/graphics/xnview was complaining about a stale dependancy. the
"shadowed " files were the compat-4-* ones. 

now , with the familiar boot, after the message: 
Mounting root from ads02
the machine wants to drop into single user mode, but it doesnt find any 
shells, instead there is the message:
/libexec/ld-elf.so.1: shared object "libncurses.so.5" not found.
I suspect, if this one was found, there were other complaints about the
other lib* files I deleted.
only the loader prompt is working, but leads in the end to the same
message.
tried the emergency shell from a 5.1 disk, but I am uncertain what to do
and do not want to screw up the data completely.

the idea is: make world again with the last sources ( current, last
update 20. or 21 april),
 as they were working nicely.
any ideas how I can get a shell ?
or another solution ?

no need to tell me about banging my head into all available
walls. :(
the machine is a notebook without floppy drive.

thanks

hans