64-bit qBittorrent crashes when using P2P filter list

This is regarding qBittorrent on a vanilla 64-bit Ubuntu Jaunty install with Boost v1.37.0-3ubuntu3. The bug is in both the 1.3.3 version (Jaunty) and also the 1.4.0 beta2. I believe this only affects 64-bit builds.

If you have a Peerguardian style filter entry with the first octet 128 or higher then qBittorrent with crash with:
terminate called after throwing an instance of 'boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<std::out_of_range> >'
  what(): address_v4 from unsigned long

The problem is in parseP2PFilterFile(). When it creates the start and last address_v4 objects it uses:
address_v4 start((IP.at(0).toInt() << 24) ...

The issue is that Boost address_v4 uses an unsigned long integer which is 64-bits. When the first octet is 128 or higher the that signed left shift will create a negative long integer which then will result in an invalid 64-bit unsigned long IP address.

One solution is to use the unsigned "toUInt()" instead of the signed version when creating address for address_v4. Another would be to cast the whole constructed IP number to a 32-bit unsigned long.

There may be more areas in the code with this same problem. Anywhere the address_v4 object is used on 64-bit builds.

To reproduce just create a p2p filter file with one entry:
Test Range:128.1.0.0-128.1.255.255