Error in Building

Dear All,
I have compiled OpenLB-0.5 with Code::blocks (an IDE for Widows with gcc compiler).
in the build process I have got such a build error:


Linking console executable: bin\Debug\olb50.exe obj\Debug\core\multiPhysics.o: In function `_ZN3olb12multiPhysics23getMultiPhysicsScalarIdIdEENS0_14MultiPhysicsIdEv':

D:/olb50/core/multiPhysics.cpp:46:
multiple definition of `olb::multiPhysics::MultiPhysicsId olb::multiPhysics::getMultiPhysicsScalarId()'obj\Debug\cavity2d.o:

D:/olb50/core/boundaryPostProcessors2D.hh:
(.text$_ZN3olb12multiPhysics23getMultiPhysicsScalarIdIdEENS0_14MultiPhysicsIdEv[olb::multiPhysics::MultiPhysicsId olb::multiPhysics::getMultiPhysicsScalarId()]+0x0): first defined here
collect2: ld returned 1 exit status


[b]and when I comment following lines (I meen double type of the similar functions in multiPhysics.cpp):[/b]

template<>
    MultiPhysicsId getMultiPhysicsScalarId<double>() {
        return DoubleScalarFieldId;
    }

the code works!
It would be grateful if anybody can help me in this problem.
Thanks!