[go-nuts] Go Server crash: slice bounds out of range

Hello!
The error "slice bounds out of range" appears When i try to send multiple
requests to the server from the client. for the first requests, every thing
is fine
this is the code that causes the error:

for client.ReadClient(buffer) {

// Check for STX and ETX
posSTX := bytes.IndexByte(buffer, 0x02)
if(posSTX==-1){
return
}

posETX := bytes.IndexByte(buffer, 0x03)
if(posETX==-1){
return
}
         Log("posSTX ",posSTX)
         Log("posETX ",posETX)


msg := string(buffer[posSTX+1:posETX-posSTX])
}

i try in this code to extract the char "0x02" and "0x03" that delimit the
  received message.
but sometimes posSTX is bigger than posETX that's what causes the error
"posSTX+1:posETX-posSTX"
anyone has an idea why it's correct for the first requests and not for the
rest??? what can be the solution for this??