I work for a company that wants to do Sybase ODBC SQL traffic over the Internet using HTTP transactions. I've developed HTTP tunneling software to enable this. The tunnel software works great. After lots of searching and refinements, I think it's just about perfect. The problem we're having is that when we operate our MFC application, which talks to the Sybase ODBC driver through the CDatabase / CRecordset layer, when we operate this, it will work fine for dozens or hundreds of operations through the tunnel, and then it will just hang up. I've got diagnostics within my tunnel software that show that there's nothing going on inside of it, and all requests have been responded to. You can see in the attached screenshots of the call stacks with the Sybase ODBC driver on them that the Sybase code is not doing anything socket/network related. Both threads with the ODBC driver on the stack are waiting on something. Running the same application and not going through the tunnel results in no problems whatsoever, it ran overnight just fine. I'm hoping that there's an expert in Sybase ODBC and HTTP tunneling who can show me the light. I think the key to solving this problem will be understanding the stack traces in the screenshots I attached. dbodbc9.dll is the Sybase ODBC driver.