Unhandled Exception on Release mode when accessing QGLFunctions::glGenBuffer

Hello all,

I'm having some trouble while compiling my project on Windows 7 using Qt 4.8 on Release mode. Everything works fine on Debug, but on Release I get an Unhandled Exception: 0xC0000005: Access violation.
I narrowed it down to the line where this happens, which is when I generate my Pixel Buffers.
My first guess would be wrong DLLs loading, but I checked the executable with Dependency Walker and every DLL loaded is correct.

Here goes some of my code:

Code:

---

class CameraView : public QGLWidget, protected QGLFunctions;
void CameraView::initializeGL()
{
 
	initializeGLFunctions(this->context());
 
	glGenBuffers(1, &pbo_); //<<<<<  This is where I get the unhandled exception on Release mode
        glBindBuffer(QGLBuffer::PixelUnpackBuffer, pbo_);
        glBufferData(QGLBuffer::PixelUnpackBuffer, 3 * sizeof(BYTE) * image_width_ * image_height_, NULL, GL_STREAM_DRAW);
        ...
}

---

Again, this works great on debug. Do you have any clue of why this is happening on Release only?

Thanks in advance,

Theo