tissue stored at -20 C -- RNA still OK?

[Juergen Brosius]

If we do not use fresh tissue for RNA preps we store it prior to prepping
at -70 C and never thaw it in between.  I have the option to use tissue of
interest that, however, had been stored at -20 C.  Does anyone have
experience concerning the state of the RNA extracted from such a source? 
I remember vaguely that a similar question was posted before but I did not
see the outcome.

Thanks in advance
                      Juergen

-- 
                                          usual disclaimers
Juergen Brosius
Inst. f. eXp. Pathol.
University of Muenster
Von-Esmarch-Str. 56
D-48149 Muenster, Germany

Fax: +49  251  83 85 12
Tel: +59  251  83 85 11