Java socket streams messing up

iv wrote a games server and it uses java socket streams to send the messages back and forth between the game clients and the game server it self
this all works great but when running and over about 5min its send over 1000 packets BUT
it will crash iv found the reason is down to when reading the packets my parser is reading wrong part and grabbing a String part when it should be a INT
now it should NEVER be reading this part of the packet so i put a trace on the packets coming in and ran it every packet was been read in perfect THEN just befor the crash TWO packets were merged together stright out from the socket stream this is y my packet reader was getting confused
what im asking is can this happen in java sockets ? i thought they were bufferered so no matter how fast you send data it would always read it out in the same order ?? not sure how its merging these to packets
is this possible of is my reader got an error in it altho works 95% of the time ??

or do you have multiple buffered streams created from the same socket?

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Thanks for your reply,
I did try to use threads with pipeStream,
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the following is the sample code I use, which I leaned from here http://home.tiscali.nl/bmc88/java/sbook/029.html
I can't found any more info regard to this topic on the internet, can you give me a hint.
thanks a lot.
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