Why an i getting this qt error ?

why an i getting this qt error when trying to compile a qt program?

i have qt2 and qt3 installed


... [compiling statements] ...

checking for extra includes... no
checking for extra libs... no
checking for libz... -lz
checking for libpng... -lpng -lz -lm
checking for libjpeg6b... no
checking for libjpeg... -ljpeg
checking for Qt... libraries /usr/lib/qt3, headers /usr/include/qt3 using -mt
checking for moc... not found
configure: error: No Qt meta object compiler (moc) found!
Please check whether you installed Qt correctly.
You need to have a running moc binary.
configure tried to run and the test didn't
succeed. If configure shouldn't have tried this one, set
the environment variable MOC to the right one before running
configure.