SMS using GET method returns a long response on RUT901

[Phono]

Hi,
I have an application that sends and receives SMS using GET commands.
I first used a RUT500, then a RUT900 and I had no problem.
I am now using a RUT901, and my application does not work anymore for SMS. After recording the TCP traffic using Wireshark, I noticed that the response to a request such as sms_total, which only returns
Used: 4
Total: 50
that is, a payload of 18 characters, actually returns a huge header before this text, such that the total TCP frame size is more than 900 bytes! I had provided a 400 byte input buffer in my application code, which was more than enough with the RUT900, but now I need a 1000 byte buffer!
Since my app is running on a microcontroller, 1K bytes is not negligible. Sure, I can set my buffer length to this value, but my question is : is there a possibility to have the RUT901 send a shorter response? Since the response is just plain text, I am a bit upset to have to receive and discard that many bytes just to access the last ones!