Does 8.3/8.4 support lazy fetched + updateable +scrollable ResultSets?

Hello,

First of all thank you for postgres. Its an amazing piece of software.

I've a legacy software which relies on updateable+scrollable
ResultSets running on postgres 7.4.
Unfourtunatly this version didn't support lazy updateable ResultSets,
so when the ResultSet is opened the whole query contents are sent to
the client at once instead of lazily - which starts to become a
serious performance problem the more data is inserted.
Does Pg 8.3 or 8.4 support lazy fetched + updateable +scrollable ResultSets?

Thank you in advance, Clemens