dates changes in Base depending upon JRE version

Binary package hint: openoffice.org-base

OOo package version : 1.2.4.1-1ubuntu2
Distro : Ubuntu 8.04 Hardy Heron

Dates entered before a certain update (in may 08) are changed to the day before ; data entered recently is not affected. (Data is entered in a date field.)

Going back to Java Runtime Environment 1.5.0_15 instead of 1.6.0_04 corrects the dates.

Formatting the dates into decimal numbers displays numbers that do not accord with Calc.

i.e. (I entered 26/05 a few days after 28/05) :

JRE 1.6
new data entered '26/05/08' is still '26/05/08' -> '39592' in Base (in Calc this nb is 24/05/08)
old data entered '28/05/08' is now '27/05/08' -> '39593' in Base (in Calc this nb is 25/05/08)

JRE 1.5
new data '26/05/08' (as entered) -> '39592' in Base (in Calc this nb is 24/05/08)
old data '28/05/08' (as entered) -> '39594' in Base (in Calc this nb is 26/05/08)

I posted before in bug 238822 but it seems to be something different.