HL6528x UDP transmission

Hi all,
I use HL6528 Development Kit for TCP/UDP data communication. The TCP (Client) is pretty good.
The UDP data is sent, but ONE UDP packet is fragmented into multiple packets at the receiver. I cannot find any config parameter for this situation.

My AT:
at+kcnxcfg=0,“GPRS”,“Apn…”,“user…”,“pa…”
OK
at+kpattern=“Z”
OK
at+kudpcfg=0,0
+KUDPCFG: 1
at+kudpsnd=1,“server.ip”,10000,5
CONNECT
[12345Z]
OK

I watch Wireshark in the Server and received 5 independent UDP packet, each 1-byte in length.
This will require more processing from Server’s software to handle UDP packet, which is ‘packet’ - not ‘stream’ like TCP.
The HL version is:
ati3
SIERRA HL6N,001.00.200E.7078D

thanks.

Is there anyone confirm this error?