/rescue/tar needing liblzma.so.2

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

I nearly locked myself out updating a server (from -6 to -8).
I booted the new kernel (single user), mounted /usr, /var and /tmp, 
extracted base.tgz (excluding /rescue, fortunately), but had forgotten 
to remount / rw.
After that (I interrupted tar), tar didn't work any more.
Well, I had /rescue/tar. Unfortunately, with z, it said
	Shared object "liblzma.so.2" not found
Fortunately, I could /rescue/gzcat base.tgz >base.tar and tar x that.

So why does something in /rescue need a shared library?