R help - Jun 2009 - ReadItem: unknown type 136, perhaps written by later version of R

Dear all,
I use at least two pc to perform my data analysis. Both are powered
with R updated at the latest release (currently 2.9.0 under windows xp
pro). I bring .Rdata on my portable drive and use them on any of my pc
(this worked also under (k)ubuntu equipped machines). Please notice
that not all my pc have the same libraries installed. If a not
installed library was called in .First() I got an warning message but
the remaining objects were loaded anyhow.

All that worked straight up to 2.8 series. Some problems arises with
2.9.0 version:

1)    .RData created with pc1 were not loaded in pc2 (pc2 cant'find
appropriate library to read .RData, I fixed that problem by installing
the appropriate package in pc2). Can't remember right now the explicit
error message, but I remember the specific package was mentioned.

2)    .RData created with pc2 is not loaded in pc1. I got this message:

Error in load("K:\\.RData") :
  ReadItem: unknown type 136, perhaps written by later version of R

I've no idea of what type 136 is. Any hints?
Thanks in advance,

Patrizio

-- 
+-------------------------------------------------
| Patrizio Frederic, PhD
| Assistant Professor,
| Department of Economics,
| University of Modena and Reggio Emilia,
| Via Berengario 51,
| 41100 Modena, Italy
|
| tel:  +39 059 205 6727
| fax:  +39 059 205 6947
| mail: patrizio.frederic at unimore.it
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