multiple get requests to the same host

Hi everybody.
A problem with my code, using libwww:
I have 2 kinds of requests, both to the same server, but with different length for their respective responses.
I wish I could issue a lot of requests, of both kinds, to the same server, avoiding the shorter responses to wait in a queue  until some huge amount of data (relative to a longer response) to be received by my application.
I used the LoadToFile function, trying to exploit pipelining and persistent connections (non blocking I/O, pseudo-threads) to enhance performance. After all my requests have been created in some kind of order (I can say it because I added a Before filter), their responses are scheduled in the same order (I can say it because I added an After filter), no short request has been serviced in an interleaving way, until a longer preceding one did.
How can I avoid such a waste waiting ?  
Thanks
Cesare Pietra