Yes. I am trying to build QtSerialPort as part of a larger project that needs to use the serial port. This project should not be required to build all of Qt4 also, and installing QtSerialPort as root is not acceptable. I need to install QtSerialPort to a user writable directory. (Specifically, it should be installed to the prefix /project/root/build/install, where QtSerialPort itself is built in something like /project/root/projects/QtSerialPort/build.)
It might be possible to use it without installing it, although that is not preferable and might cause other problems down the road (e.g. when we need to build installers for this project).
For the moment I am just ignoring the qmake project files and have rolled my own build system for QtSerialPort using CMake, which natively supports an install prefix.