Qt + Google Protocol Buffers, Trouble linking libraries

Hopefully this is an easy question:

I am building an application with Qt and would like to use Google's Protocol Buffers. I have downloaded and installed the protobuf source, now I开发者_Python百科 want to link against it in my project.

My .pro file contains the line:

LIBS += -L/usr/local/lib -libprotobuf

However, I get the error:

:: error: library not found for -llibprotobuf

when trying to compile.

I am assuming that I am doing something rather basic wrong. Thanks for any help!

---

Assuming the file is libprotobuf.[so|a], the correct library link command is -lprotobuf (the lib prefix is implied)