How to truncate http request size to minimum?

To save GPRS traffic, I wan't to delete some headers from my midlet's request. For example, if regular response headers looks like this:

then it would be great to truncate such headers to something like this:

If I try to do

then it takes no changes into resulting Http Request Headers - User agent stays as it was - Nokia5310XpressMusic/2.0 (05.81) Profile/MIDP-2.1 Configuration/CLDC-1.1 UNTRUSTED/1.0

In API docs of HttpConnection interface, there is written:

setRequestProperty
public void setRequestProperty(String key,
String value)
throws IOException
Sets the general request property. If a property with the key already exists, overwrite its value with the new value.

Looks like Nokia add that user-agent header right before connection is opening. So how to avoid this? How to truncate these headers to minimum?

ok, never mind, ill do SocketConnection instead of HttpConnection