Created attachment 26744 [details]
An example of the bug. Watch the formula and then edit it.

Basically, when I look into the saved document, it looks like the formula was
created with SO/OOo and *afterwards* modified with a different program.
If that's the case, well then basically you can't expect the formula to be read
correctly anymore.
Thus unless you can exactly tell how to reproduce this kind of formula problem
with only using SO/OOo there is nothing that could be done about it.

Therefore please specify how to reproduce this and then assign it back to me.

It is all written in OO.org version m680-104. 
No other program. It didn't even go through the "save as sxw" filter. 
 
If it looks like there was interference with other program, then this 
interference is introduced by OOo. 
 

I can confirm this issue in M109.  Interestingly after looking at your file I 
noticed that it changes the equals sign to a  def  Can you post what you type 
into the formula editor to get the result your after?  This will help in 
reproducing the bug outside your document and determining where it actually 
lies.

Adam

Confirmed again on m113 on Linux x86 (FC3). 
Regarding the 'def' '=' issue. this is indeed interesting. I just realized 
that the signs are '=' instead of 'def'. As soon as you edit it though - it 
turns to 'def', and the formula truncates. 
I believe I wrote 'def' originally, but i have no way to tell. 

This issue is worksfrome.

The content of the document only contains the "shorter" formula, so somehow the
preview-image got out-of-date.

Maybe the formula was edited using a macro or something without updating the
preview, or there was a crash and the recovery took an updated image and the old
formula-"source" or vice versa.

In any case: OOo doesn't truncate the formula, but corrects the display of the
formula to reflect the actual contents of the document.

Form the document and the description it is impossible what went wrong. I can
only tell that the formula is already truncated in the file.

BTW: regarding the "=" vs "def" issue: "def" is what is written in the document.

Unless you can give a step-by-step instruction on how to reproduce this error
(i.e. how to make OOo not save the entered formula but a different one), nothing
can be done about this.

But given the fact that OOo doesn't only truncate the formula, but replaces it
by something different, I guess it is due to a faulty/partial crash recovery or
some other influence.

closing since OOo doesn't do anything wrong when opening or editing the attached
document.

I took the bother and typed again the entire equation in 1.9.122. 
There was no problem, so closing is fine with me ...