I use proxy over http ,but always return -33(time out).

code :

iSession.OpenL());
TBuf8<20> aProxy8(_L8("10.0.0.172:80"));

RStringF iPrxAddr = iSession.StringPool().OpenFStringL(aProxy8);
CleanupClosePushL(iPrxAddr);

THTTPHdrVal iPrxUsage(iSession.StringPool().StringF (HTTP::EUseProxy,RHTTPSession::GetTable()));

iSession.ConnectionInfo().SetPropertyL(iSession.StringPool().StringF(HTTP::EProxyUsage,RHTTPSession::GetTable()), iPrxUsage);
iSession.ConnectionInfo().SetPropertyL(iSession.StringPool().StringF(HTTP::EProxyAddress,RHTTPSession::GetTable()), iPrxAddr);
CleanupStack::PopAndDestroy();
......
RStringF method = iSession.StringPool().StringF(HTTP::EPOST,RHTTPSession::GetTable());
iTransaction = iSession.OpenTransactionL(uri, *this, method);
RHTTPHeaders header = iTransaction.Request().GetHeaderCollection();
SetHeaderL(header, HTTP::EUserAgent, KUserAgent);
SetHeaderL(header, HTTP::EAccept, KAcceptAny);
SetHeaderL(header, HTTP::EContentType, KAcceptWbx);
SetHeaderL(header, HTTP::EConnection, KConnection);
iPostBody = aBody.AllocL();
iTransaction.Request().SetBody(*this);
iTransaction.SubmitL();
....

handset: P802
sdk: Symbina70UIQ2.0

why???????