> try {
> db.socket = new Socket(dbai.getServer(),

dbai.getPort());

> db.socket.setReceiveBufferSize(16 * 1024);
> db.socket.setSendBufferSize(16 * 1024);

Exactly, this is the right place. However it seems that you have old
source. There must be one more line:

db.socket.setTcpNoDelay(true);

This code must look like this:

try {
db.socket = new Socket(dbai.getServer(), dbai.getPort());
db.socket.setTcpNoDelay(true);
db.socket.setReceiveBufferSize(SOCKET_REC_BUF_SIZE);
db.socket.setSendBufferSize(SOCKET_SEND_BUF_SIZE);
if (debug) log.debug("Got socket");
} catch (UnknownHostException ex2) {
String message = "Cannot resolve host " + dbai.getServer();
if (debug) log.error(message, ex2);
throw new GDSException(ISCConstants.isc_arg_gds,
ISCConstants.isc_network_error
, dbai.getServer());
}

Note, I have defined two constants: SOCKET_REC_BUF_SIZE and
SOCKET_SEND_BUF_SIZE.

Also, it would be better if you check out complete driver sources,
not only GDS_Impl.java. This can be done using cvs:

cvs -d :pserver:anonymous@...:/cvsroot/firebird login
cvs -d :pserver:anonymous@...:/cvsroot/firebird co client-java

then you can run client-java/build.bat or client-java/build.sh

> Roman, can you make changes and check driver?

No, this is not a bug fix, and we are already in release phase.

Best regards,
Roman Rokytskyy