short packets?

I have Windows Server 2003 running on a SUN X2100 (AMD based) server. I have
an application that we have found the socket implementation
on the SUN server creates an interrupt on every packet (512 bytes)
receipt versus buffering all the data received so we can read
sysread mode of a certain buffer size) as may bytes as we request
from the buffer. Is there something I can set in the registry here to help?
I have verified the network, I'm sure the data is making it to the server.