[Histonet] related question; but FREEZE- Formalin fix---then freeze?

[DANIEL EBERHARD]

Dear Histonetters,
I have a succeeding question to the "formalin-freeze" topic.
Accidentally some mouse tissues (with cytosolic and highly soluble GFP),
which I routinely pre-fix in pFA, wash and freeze, were frozen without 
pre-fixation (stored at -80°C).
Now, I would like to *thaw *the tissue, *fix it* (pFA) and *freeze* it 
again, but of course thawing (e.g. crystal formation)
might ruin cells and membranes, so that the GFP might pour out. Thus, 
I´m searching for some tips now to manage this?
Has anyone done sth. like this before?
"Post-pFA-fixation" of sections is unfortunately impossible.

Thanks for any tips and tricks.
Daniel.