Please describe the problem:
When using gnucash while traveling across time zones, strange things happen to the data file.

My 2314-transaction datafile gets all (or most) of its dates rewritten in the following way:

   <trn:date-posted>
-    <ts:date>2005-02-28 00:00:00 -0700</ts:date>
+    <ts:date>2005-02-28 02:00:00 -0500</ts:date>
   </trn:date-posted>
   <trn:date-entered>
-    <ts:date>2005-03-01 08:17:48 -0700</ts:date>
+    <ts:date>2005-03-01 10:17:48 -0500</ts:date>
   </trn:date-entered>

I keep my uncompressed data file under version control, and this causes ridiculously large commits every time I save my data while in a different time zone.

Steps to reproduce:
1. Have a pre-existing data file A with transactions and a price database
2. Change your computer's time zone.
3. Open data file A. *do not edit anything*
4. Save data file A.
5. A lot of information gets changed.

Actual results:
A lot of information gets changed.
For each transaction (as far as I can tell,) a pair of time stamp changes as above occur, in addition to time stamps for reconciliation data and price database entries.

Expected results:
Only information I've actually changed should get changed. In particular, the steps to reproduce should not result in any changes to the datafile.

Does this happen every time?
This happens every time on Mac OS X 10.4.
I expect this would happen on other unixes as well, but I have not tested any.

Other information:
This is related to bug 137017: http://bugzilla.gnome.org/show_bug.cgi?id=137017

However, I believe that they are be different because 137017 is an UI issue, while this is a back-end/storage issue that results in frivolous changes to the underlying data.

Here's a guideline: if the user does not change the data, the software should not change the data either.