(keitai-l) possible to receive streaming-data with httpConnection?

Hello all,

I am developing for european i-mode.
Now I am trying to develope some server-client application. Here comes 
the problem:
I want to realize some server-client communication (just like for 
instant messaging, chat) without polling too many times.

So I thought of sending one http request (post/get) for a php-file which 
has executing time of 1 minute. So I can receive data of 1minute without 
polling again.
That php-file appends some new data every 10seconds to the 
"already-outputted" data.
I am using php command  sleep() for that.

On normal PC-Web there's no problem with that but my i-appli just 
refuses to receive the data.
The request for that php-file so far looks good but then no answere/ no 
receiving data.

Thank you very much in advance,

Noriyasu