Deprecated warnings still appear

I compile the same code on both Mac OS X Leopard and on Linux Ubuntu, with the same lines in the .pro file:

Code:

---

QMAKE_CXXFLAGS_DEBUG += -Wno-deprecated
QMAKE_CXXFLAGS_RELEASE += -Wno-deprecated

---

No deprecated warning appears on the Mac but they appear on Linux, which is really annoying.
Any help?