quickfix performance

Hi Steve,
We are trying to evaluate using QF engine using java api and found new issues. The message creation by just using the data dictionary that comes with FIX.4.2.xml is taking longer than just adding required fields. Our application is very powerful and don't want to add any extra latency. But, when I did some stats, I found QF message creation takes longer time (say for MktdataIncRefresh) if I use groups. I changed the Message.java where I can now do addfield as list and create the message witout using Groups. That's 3 times faster. I understand that the way the java code is written and really superb. But, it affected the performance in big time.

say if I want
1) add desired fields
2) add groups as a list

currently I can't do it with QF. I have to use setField and addgroup methods.

also I found another prb where the send and processmessage methods are synchronized. I guess this is done for sequence numbers. why do we want to lock the object by putting synchronized in the methods?

pls advise. I am anyway going to change as per my requirements.

Thanks for all the great help and support..

Cheers
Rohit