Wireshark-users: [Wireshark-users] Retransmitted packet with different lenght

From: Amir Ahmadi <a_h_ahmadi@xxxxxxxxx>
Date: Sun, 14 Feb 2010 08:04:33 -0800 (PST)
Hello

I have a problem.
I have two server (called server A and B).
When i sniff packets between these two servers, I found that server A send a data 7 times(with 7 packets). these packets have same Seq and ACK numbers, the time between first ant last packet are about 6 second and in this time Server A has not received any packets. but their length is not the same(some of them are same). I write 4 collection of data in socket in server A and all of them are in one packet.
now, I want to know that these packet (that have same Seq and ACK numbers) are retransmitted packets? is have different length a problem?
And, I want to know that, if these are retransmitted packets, why do some of these packet(3 packets) have data that part of 3th data collection and all of 4th data collection is not in those packets?
I wrote my Application on server A by java, I don't know where this problem happened(OS Level, JVM Level, Application Level, TCP Level or ...)?

I'll be glad for your replies.

Regards.
A-h.Ahmadi