To take advantage of all the new features in ConfigMgr 2007 R3 you need to udpate the ConfigMgr Client Agent. Here are the steps to add the KB977384 update to the ConfigMgr Task Sequence.
Step-by-step instructions
- After installing the KB977384 update on the ConfigMgr 2007 server, make a note of the ConfigMgr Client Package ID. In my environment the Package ID was C010000E.
- Refresh (Or Update) your ConfigMgr Client Package. This is needed since the KB977384 adds new files to the ConfigMgr Client Package.
- Edit your Task Sequence, and in the Setup Windows and ConfigMgr action, in the Installation Properties textbox, type in the following
PATCH="C:_\SMSTaskSequence\OSD\C010000E\i386\hotfix\KB977384\sccm2007ac-sp2-kb977384-x86-enu.msp"Note: Replace the C010000E with the package ID in your environment
- Done.
After deployment the ConfigMgr Client version should be 4.00.6487.2157 – See the general tab of the ConfigMgr 2007 Client control panel applet (SMSCFGRC.CPL).

Resources
Description of the prerequisite hotfix for System Center Configuration Manager 2007 R3
http://support.microsoft.com/kb/977384
/ Johan